Yet Another Cycling Forum

Off Topic => The Pub => Topic started by: hellymedic on 01 August, 2014, 03:53:23 pm

Title: Arithmetic that makes you cringe
Post by: hellymedic on 01 August, 2014, 03:53:23 pm
I do wish the journos reporting this tragic story could count!
http://www.bbc.co.uk/news/uk-england-28611078 (http://www.bbc.co.uk/news/uk-england-28611078)
Title: Re: Arithmetic that makes you cringe
Post by: David Martin on 01 August, 2014, 04:08:29 pm
They can - they have rounded down to whole years. It wasn't 13 years
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 01 August, 2014, 05:11:45 pm
They appear to have edited the wording from 'ago' to 'later'...
Title: Re: Arithmetic that makes you cringe
Post by: Diver300 on 02 August, 2014, 09:20:06 am
From an official document published by a large manufacturing company, later revised when I told them about it:-

0.01% failure rate (1000 ppm)

Title: Re: Arithmetic that makes you cringe
Post by: citoyen on 08 August, 2014, 09:42:31 pm
I think it might have been mentioned in another thread at the time but there was a Co-op ad recently that claimed a bank holiday weekend was a third longer than a regular weekend.

:facepalm:
Title: Re: Arithmetic that makes you cringe
Post by: Asterix, the former Gaul. on 09 August, 2014, 08:30:19 am
Well it is a third day longer..
Title: Re: Arithmetic that makes you cringe
Post by: Andrij on 11 August, 2014, 09:33:01 pm
(https://scontent-b-ams.xx.fbcdn.net/hphotos-xpf1/t31.0-8/q79/s720x720/1939433_1023685690994217_8033129593823460003_o.jpg)
Title: Re: Arithmetic that makes you cringe
Post by: David Martin on 11 August, 2014, 09:43:00 pm
So? There are many places that sell coffee but do not have a store.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 28 August, 2014, 10:49:50 am
Quote
A surge in immigration from within the European Union (EU) was behind the increase as two-thirds of all immigrants to the UK in the period - 214,000 out of 560,000 - came from within the EU.
From today's Telegraph. Just as likely to be cringeworthy editing/proofreading probably, but still...
Title: Re: Arithmetic that makes you cringe
Post by: CommuteTooFar on 28 August, 2014, 12:56:10 pm
My company forgot last years promised 6% pay rise so I grumbled. So they said this year they would pay me 6% and 4% = 10% this year. Surely 10% is 6% and 3.77%.
Title: Re: Arithmetic that makes you cringe
Post by: lastant on 28 August, 2014, 01:45:48 pm
Recently decided to purchase a Jawbone UP24 to do a bit of quantified self-ing (mostly interested in the sleep monitoring / reporting) having got some Love2Shop vouchers to use up.

I then spotted I could order it in to my local Halfords, which meant I could also use my British Cycling discount. Every little helps etc..

List price of £104.99, the girls on the till between them decide to not simply scan in the barcode for the BC discount but enter it manually. I quote: 'So, ten percent of that. That's...twelve pound fifty'.

Nice little bonus for me, just disappointing when it's one of those simple ones to calculate!
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 28 July, 2016, 05:42:27 pm
From today's Independent.
http://www.independent.co.uk/news/uk/politics/uk-police-shooting-statistics-discharge-firearms-figures-freddie-gray-baton-killings-homicide-a7160391.html (http://www.independent.co.uk/news/uk/politics/uk-police-shooting-statistics-discharge-firearms-figures-freddie-gray-baton-killings-homicide-a7160391.html)

British Police fire guns 7 times in one year.
British population 64M
USA population 319M
Quote
The United States of course has a bigger population than the UK – Britain has 64.1 million residents, the US 319 million. But on a per-capita basis, Britain’s rate of police gun use would translate into US police using their guns on 84 occasions in an entire year. This would be an unthinkably low number.

How does 7 * 5 = 84?
Title: Re: Arithmetic that makes you cringe
Post by: Bledlow on 28 July, 2016, 06:46:50 pm
My company forgot last years promised 6% pay rise so I grumbled. So they said this year they would pay me 6% and 4% = 10% this year. Surely 10% is 6% and 3.77%.
Not necessarily. Depends on how they calculate it. 6% of your salary plus 4% of your pay before the 6% raise is 10%.
Title: Re: Arithmetic that makes you cringe
Post by: PhilO on 28 July, 2016, 07:59:40 pm
Almost any advertisement claiming a discount...

"Everything up to 50% off!!!"

 ::-)
Title: Re: Arithmetic that makes you cringe
Post by: ElyDave on 28 July, 2016, 08:03:20 pm
Not quite arithmetic, but "it's Thursday, welcome to the start of finals week on masterchef"

Surely midway through finals week?
Title: Re: Arithmetic that makes you cringe
Post by: TheLurker on 29 July, 2016, 10:10:46 am
The start of a maths lesson, 197{ahem!}; a maths teacher flinging marked homework jotters at pupils.  He arrives at that belonging to a Boy Lurker...

 Boy Lurker!  3 times 3?
 Boy Lurker, rapidly and confidently, six sir.
 *A moment's silence for the awful truth to sink in.*
A pitying look from the maths teacher as the Boy Lurker cringes at his desk whilst his school-fellows pour (well deserved) scorn and derision upon him.

I had made _exactly_ the same error in the homework, I'd done all the hard stuff (chiz algebra) perfectly but stuffed up basic arithmetic.  Over the years MrsLurker has come to recognise that my arithmetic is a little, umm, fuzzy and does our accounts.  It's probably for the best. :)
 
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 29 July, 2016, 05:53:42 pm
Almost any advertisement claiming a discount...

"Everything up to 50% off!!!"

 ::-)
Even worse (for the customer), something like 'up to -25% discount'. Seen it only once and decided to pass on by.
Local shoe shop offered BOGOF - um?
Title: Re: Arithmetic that makes you cringe
Post by: Bledlow on 29 July, 2016, 07:03:25 pm
Free left with every right!
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 29 July, 2016, 08:08:06 pm
I've seen BOGOF on eyebrow threading, which makes even less sense than shoes.
Title: Re: Arithmetic that makes you cringe
Post by: Basil on 29 July, 2016, 08:15:26 pm
Surely BOGOF on shoes, eyebrows and any other obviously pairs are simply an attempt at humour.  I remember the surgeon trying to make the same joke DURING my vasectomy years ago.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 29 July, 2016, 08:17:23 pm
Surely BOGOF on shoes, eyebrows and any other obviously pairs are simply an attempt at humour.  I remember the surgeon trying to make the same joke DURING my vasectomy years ago.

To be fair, you don't want actually funny jokes during a vasectomy...
Title: Re: Arithmetic that makes you cringe
Post by: Basil on 29 July, 2016, 08:27:21 pm
Good point.
Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 29 July, 2016, 08:37:43 pm
No, TV's Henry Coles, a motorcycle introduced in 1958 is 58 years old.  That, by any stretch of the imagination, is not "nearly 70".
Title: Re: Arithmetic that makes you cringe
Post by: Feanor on 29 July, 2016, 08:38:00 pm
Mrs F was never that much into Numbers and all.
She had to do a Tax module at Law School back in the day.

I remember trying to help out with the basic problem:

If something costs £100, and we add 10% tax, it then costs £110. That's fine.
But why can't I just remove the tax element by removing 10% of the £110?

She's still not convinced about the arithmetic, and suspects alien involvement.
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 29 July, 2016, 08:52:31 pm
No, TV's Henry Coles, a motorcycle introduced in 1958 is 58 years old.  That, by any stretch of the imagination, is not "nearly 70".

I too am that age and of that vintage.

I am CERTAINLY NOT 'nearly 70'!
Title: Re: Arithmetic that makes you cringe
Post by: TheLurker on 29 July, 2016, 09:37:24 pm
No, TV's Henry Coles, a motorcycle introduced in 1958 is 58 years old.  That, by any stretch of the imagination, is not "nearly 70".
I dunno 58 is nearly 60 which is the same order of magnitude as 70 sooo if you wave your hands enough it is nearly(ish).  :)

Entirely irrelevant aside.  Saw him, that Cole bloke, with his mate Sam this lunchtime at The Plough at Kelmscott.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 30 July, 2016, 08:00:25 am
2016-1947 = 69.  That makes me cringe.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 30 July, 2016, 09:51:18 am
No, TV's Henry Coles, a motorcycle introduced in 1958 is 58 years old.  That, by any stretch of the imagination, is not "nearly 70".

I too am that age and of that vintage.

I am CERTAINLY NOT 'nearly 70'!
Perhaps fair enough when you're talking about a motorcycle and want to emphasise how amazingly advanced it was.
"Despite being designed 58 years ago, the Norazuki 500 Death Star Red Dwarf is technologically identical to a modern motorcycle, featuring overhead valves, electronic ignition and an early form of antilock braking."
Sounds quite impressive.

"Despite being born 58 years ago, Helen is anatomically identical to a modern human, featuring stereoscopic eyes, opposable thumbs and an early form of bipedal locomotion."
Hmmm...
Title: Re: Arithmetic that makes you cringe
Post by: Steph on 30 July, 2016, 09:22:08 pm
I was born in 1958, and am 58. I find that curiously satisfying, and symmetrical
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 31 July, 2016, 08:48:54 am
So do I!
But
I am not 'nearly 70'.
We have outlived Prince and Michael Jackson born that year.
Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 31 July, 2016, 09:13:12 am
Surely BOGOF on shoes, eyebrows and any other obviously pairs are simply an attempt at humour.  I remember the surgeon trying to make the same joke DURING my vasectomy years ago.

To be fair, you don't want actually funny jokes during a vasectomy...
I dunno. During mine, the crool  nurse showed me the first bit of tube they had snipped out, balanced on the tip of her gloved finger.
"Don't touch me" she warned "I'm sterile "

"And I soon will be" I replied, as they moved from left bollock to right.
Title: Re: Arithmetic that makes you cringe
Post by: Mrs Pingu on 29 August, 2016, 09:46:01 pm
Quote
Opinions vary on how many children grow up thinking the wrong man is their father, but German studies put the figure at between less than 4% and more than 10%.

So  0-4% or 10-100% then? But definitely not 5-9%  :facepalm:

https://www.theguardian.com/world/2016/aug/29/germany-plan-force-mothers-reveal-childs-biological-father
Title: Re: Arithmetic that makes you cringe
Post by: David Martin on 29 August, 2016, 11:27:27 pm
No, between a number less than 4 and a number greater than 10, so definitely including the range 4-10 but maybe not including the ranges 0-4 and 10-100
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 30 August, 2016, 09:16:51 am
Re. the test of autonomous cars in Singapore: the area is only 2 square kilometres (OK so far) on a side(!)
Title: Re: Arithmetic that makes you cringe
Post by: mattc on 30 August, 2016, 12:26:07 pm
No, between a number less than 4 and a number greater than 10, so definitely including the range 4-10 but maybe not including the ranges 0-4 and 10-100
Well deciphered.



Its almost certain that this one was the work of an innumerate journo (i.e. most of them). But this would have been so easy to fix with the little word "about" (or even "roughly").

Frustrating, but not surprising.
Title: Re: Arithmetic that makes you cringe
Post by: jsabine on 30 August, 2016, 03:35:14 pm
No, between a number less than 4 and a number greater than 10, so definitely including the range 4-10 but maybe not including the ranges 0-4 and 10-100
Well deciphered.



Its almost certain that this one was the work of an innumerate journo (i.e. most of them). But this would have been so easy to fix with the little word "about" (or even "roughly").

Frustrating, but not surprising.

I thought it was awkwardly phrased rather than innumerate - and not even that hard to decipher.

But I'd have gone for something like "at least around 1 in 25, but perhaps as many as 1 in 10 ..."
Title: Re: Arithmetic that makes you cringe
Post by: Mrs Pingu on 31 August, 2016, 06:22:05 pm
No, between a number less than 4 and a number greater than 10, so definitely including the range 4-10 but maybe not including the ranges 0-4 and 10-100

Well I know that, but surely the thing to say would have been between 3 and 11%!
Title: Re: Arithmetic that makes you cringe
Post by: Feanor on 31 August, 2016, 08:15:17 pm
I've spent much of the afternoon trying to make sense of someone else's code in relation to units.
The Help File and the Program were inconsistent, and investigation with actual numbers became a maze of twisty passages.

The code can take inputs in a variety of units ( typical oilfield nonsense ), and generates simultaneous outputs in various units which seemed to be incorrectly labelled.  It seemed the code was producing the correct answers, but in orders of magnitude wrong ( ie the units were incorrectly prefixed with K or M )

The decoding of this required a bunch of head-scratching as to what they authors actually meant.
Here are some examples:

hm3. (Hecto-metres) cubed. Not Hecto (Meters cubed). 100m x 100m x100m. 1 hm3=1000000 m^3.

MMBBL. 10^6 ( one Million ) Stock Tank Barrels. A Barrel is BBL. But in Awl Field Talk, a Million is prefixed MM sometimes. Not just M.

Bft3. Billion ( 10^9 ) Standard Cubic Feet.
Title: Re: Arithmetic that makes you cringe
Post by: Mrs Pingu on 31 August, 2016, 08:24:27 pm
And an Mbbl is 1000 bbls. Bloody confusing until you get used to it.

But then go to world of corrosion where they quote corrosion rates interchangeably as either mpy or mmpy, where mpy is 1/1000 of an inch per year and mmpy is a millimeter per year.   :facepalm:
Title: Re: Arithmetic that makes you cringe
Post by: David Martin on 31 August, 2016, 10:49:31 pm
Given the accuracy of corrosion prediction, does that factor of 25(ish) matter?
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 01 September, 2016, 12:24:22 am
There's a dedicated circle of hell for this stuff, isn't there?
Title: Re: Arithmetic that makes you cringe
Post by: Bledlow on 01 September, 2016, 12:30:49 am
If there isn't, there should be.
Title: Re: Arithmetic that makes you cringe
Post by: ElyDave on 01 September, 2016, 08:21:36 am
If there isn't, there should be.

There is, it's called the EU emissions trading shecme (EUETS) where I'm required to verify operator's emissions in tonnes of CO2, but they use units like those above.

MMscf ffs  :demon:

The biggest issue is things like Feanor's above where folks take in stuff in volume, do stuff to it and try and spit out something else at the end.  Teh problem is that many of them (reservoir engineers in partic) have a very fixed view of the world and use fixed factors in their code that screw things up.

Doing everything in mass is much more sensible as that is conserved throughout, only do mass/vol conversions right at the end and use up to date factors
Title: Re: Arithmetic that makes you cringe
Post by: Mrs Pingu on 01 September, 2016, 12:25:12 pm
Given the accuracy of corrosion prediction, does that factor of 25(ish) matter?

God alone knows. I try to keep away from the rust department as much as possible.
Title: Re: Arithmetic that makes you cringe
Post by: clarion on 02 September, 2016, 09:40:03 am
About 40 thou to a mm, isn't it?
Title: Re: Arithmetic that makes you despair
Post by: hellymedic on 25 January, 2017, 08:42:50 pm
University nearly kills studes with caffeine...
http://www.bbc.co.uk/news/uk-england-tyne-38744307 (http://www.bbc.co.uk/news/uk-england-tyne-38744307)
Title: Re: Arithmetic that makes you cringe
Post by: ElyDave on 25 January, 2017, 09:06:57 pm
I read that one, both humorous and  :o at the same time
Title: Re: Arithmetic that makes you despair
Post by: redshift on 25 January, 2017, 09:36:04 pm
University nearly kills studes with caffeine...
http://www.bbc.co.uk/news/uk-england-tyne-38744307 (http://www.bbc.co.uk/news/uk-england-tyne-38744307)

Back in the dim and distant past, when I was pretending to be doing a degree in Biochemistry and Chemistry, we were regularly presented with a list of the chemistry we would be using in upcoming labs.  The idea was then to attend the library and consult such fabulous references such as N. Irving Sax's 'The dangerous properties of industrial chemicals' or the Merck Index, or similar works, and write up a complete safety audit for each chemical we were going to use, including what to do if it was spilled or ingested.  Not presenting a safety audit resulted in not doing the lab, and this was in the 80's, long before elfin safety and risk assessments were anything like as prevalent as today.  I remember having to look up caffeine for one experiment, and finding new respect for the fine white crystals that filled the sample tube at the end of the day.  The story reads like there were neither safety audits nor supervision for that experiment - an audit alone should have primed someone to notice that they were out by a factor of 10, based on LD50 alone, surely?
Title: Re: Arithmetic that makes you cringe
Post by: barakta on 25 January, 2017, 09:55:35 pm
I have a friend who has been a postdoc at a few unis and she says H&S can be shocking in some places. There is limited supervision of younger students and researchers and when stuff goes wrong coverups are massive. Cutting corners only works for so long.

I hope other unis are reading that and thinking "SHIT, we'd better look at ourselves carefully too".
Title: Re: Arithmetic that makes you cringe
Post by: Manotea on 25 January, 2017, 10:08:51 pm
True story in (long) post decimal Britain....

Customer: 100 rolls please...

Rolls cost 4p each.

Shop Assistant to friend: What's 4 times 100?
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 25 January, 2017, 11:30:24 pm
True story in (long) post decimal Britain....

Customer: 100 rolls please...

Rolls cost 4p each.

Shop Assistant to friend: What's 4 times 100?


Can't be that long post-decimal if rolls anything costs 4p thobut.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 25 January, 2017, 11:35:32 pm
"Rolls of what?" was my first thought.
 :D ;) ::-) :facepalm: ;D
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 25 January, 2017, 11:42:45 pm
SMD resistors, maybe...
Title: Re: Arithmetic that makes you cringe
Post by: Feanor on 25 January, 2017, 11:46:30 pm
There are plenty of scams that rely on people not being able to do arithmetic.

That's £10:84, please.
OK, I'll give you £20.84, and you give me a tenner back.
Ah, I don't have the 84. So i'll give you this shilling and a thruppney, and you can give me a groat back, if I take back my original £20 and give you a tenner and a groat instead. And there's a sheckel in it for you too.

Err...

This is why modern tills are programmed to try deal with this kind of thing.
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 26 January, 2017, 01:12:14 am
True story in (long) post decimal Britain....

Customer: 100 rolls please...

Rolls cost 4p each.

Shop Assistant to friend: What's 4 times 100?


Graves' rolls were 3p when I was a young Penniless Student Oafette in 1976, rising to 5p by 1981.
Trufax.

If this had been around 1978, decimalisation would have been 7 years previously...

Can't be that long post-decimal if rolls anything costs 4p thobut.
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 26 January, 2017, 08:47:10 am
Graves' rolls were 3p when I was a young Penniless Student Oafette in 1976, rising to 5p by 1981.
Trufax.

There's a Viz Top Tip along the lines of "keep all of your till receipts so that you can bore your grandchildren with greater accuracy in years to come"  Were you an early adopter of this advice, helly?  ;)
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 26 January, 2017, 01:16:43 pm
Graves' rolls were 3p when I was a young Penniless Student Oafette in 1976, rising to 5p by 1981.
Trufax.

There's a Viz Top Tip along the lines of "keep all of your till receipts so that you can bore your grandchildren with greater accuracy in years to come"  Were you an early adopter of this advice, helly?  ;)

 :) ;) ;D  No.

I sometimes have a very retentive memory thobut.
I wasn't even particularly Penniless, though managing my own budget was was a new experience.
Sheffield was cheap, student grants were generous and having multiple sibs in Higher Education cut parents' contribution considerably.
I became adept at making a Little Money Go A Long Way, which was easy then.
This was useful when Parents Stopped All Money as I had been Naughty.

Rice Pudding Hallamshire Hospital 4p/bowl...
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 12 February, 2018, 09:04:28 pm
From the lovely Bournemouth Echo.
Nursing home loses £8,000 per week which is '£32,000 per quarter'.

I thought there were 13 weeks in a quarter and 8,000 x 13 = £104,000.

Did she mean a (short) month?

http://www.bournemouthecho.co.uk/news/15987698.__39_It__39_s_a_shambles__39___NHS__39__new_patient_discharge_system_leaves_care_home_facing_closure/?ref=mr&lp=15 (http://www.bournemouthecho.co.uk/news/15987698.__39_It__39_s_a_shambles__39___NHS__39__new_patient_discharge_system_leaves_care_home_facing_closure/?ref=mr&lp=15)
Title: Re: Arithmetic that makes you cringe
Post by: Pingu on 29 November, 2018, 12:59:55 pm
https://www.theguardian.com/environment/2018/nov/29/four-years-hottest-record-climate-change

Quote
Average temperatures around the world so far this year were nearly 1C (33.8F) above pre-industrial levels.

 :facepalm:
Title: Re: Arithmetic that makes you cringe
Post by: Si S on 29 November, 2018, 01:06:40 pm
https://www.theguardian.com/environment/2018/nov/29/four-years-hottest-record-climate-change

Quote
Average temperatures around the world so far this year were nearly 1C (33.8F) above pre-industrial levels.

 :facepalm:

Probably should be grateful they aren't up 274.15 kelvin
Title: Re: Arithmetic that makes you cringe
Post by: Greenbank on 29 November, 2018, 01:13:03 pm
Never trusted those Foreignheits.
Title: Re: Arithmetic that makes you cringe
Post by: citoyen on 29 November, 2018, 01:16:26 pm
https://www.theguardian.com/environment/2018/nov/29/four-years-hottest-record-climate-change

Quote
Average temperatures around the world so far this year were nearly 1C (33.8F) above pre-industrial levels.

 :facepalm:

That is brilliantly daft.

Probably should be grateful they aren't up 274.15 kelvin

Anyone who watched the last series of Bake Off will have seen the little Amazon Alexa ads that bookended each commercial break. One of them had Our Intrepid Baker asking "Alexa, what's the boiling point of sugar?" to which Alexa replies "The boiling point of sugar is XXX degrees."

Now, leaving aside the fact that the question is nonsensical, since sugar doesn't have a boiling point as such, it really infuriated me that Alexa didn't specify the scale in her answer - I can't recall the exact figure quoted but I'm sure it must have been in Fahrenheit, which shouldn't be too surprising given that Alexa is Transpondian, but a) my old maths teacher would have given her a clout round the ear for such sloppiness, and b) it's the 21st feckin' century so use Celsius already. Anyway, I amused myself by imagining that Our Intrepid Baker guessed that Alexa was working in Kelvin and so put their sugar solution in the freezer to boil it...
Title: Re: Arithmetic that makes you cringe
Post by: ElyDave on 29 November, 2018, 01:53:04 pm
Of course sugar has a boiling point,

which must be specified based on the exact composition i.e. a solution of x% w/w sugar in water boils at YY deg C at ZZ pressure.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 29 November, 2018, 01:55:23 pm
Of course sugar has a boiling point,

which must be specified based on the exact composition i.e. a solution of x% w/w sugar in water boils at YY deg C at ZZ pressure.
Even then it's going to vary from batch to batch isn't it, what with sugar being a plant-produced compound and not just the same thing always?

Anyways, the original story is wonderfully silly.
Title: Re: Arithmetic that makes you cringe
Post by: citoyen on 29 November, 2018, 02:02:03 pm
Of course sugar has a boiling point,

which must be specified based on the exact composition i.e. a solution of x% w/w sugar in water boils at YY deg C at ZZ pressure.

My understanding is that dry sugar granules don't have a boiling point as such - they just break down into caramel when heated.

Sugar solution is a different matter.

Perhaps it's a question of terminology. I'm coming at this from a cook's perspective, not a chemist's.
Title: Re: Arithmetic that makes you cringe
Post by: mattc on 29 November, 2018, 02:28:41 pm
I'm not sure of the right terminology, but it may be that solid sugar does sublimation, not boiling*:

https://en.wikipedia.org/wiki/Sublimation_(phase_transition)

*Of course it's more complicated than that - and this is all physics, not chemistry IMHO!
Title: Re: Arithmetic that makes you cringe
Post by: Greenbank on 29 November, 2018, 02:42:34 pm
Quote from: https://www.quora.com/What-is-the-melting-and-boiling-point-of-sugar
Sugar does not melt or boil, it decomposes. For sugar to have either it would have to retain its molecular formula which it does not. When it is heated it is carmelized.

Caramel has a boiling point, so that's probably what Alexa's answer was. More specifically, the answer to the question: If you heat sugar in a pan at what temperature does the stuff in the pan start to boil?

But the solid->liquid stage is not reversible if caramelisation has taken place. If you cool molten caramel down it does not become sugar again.

Another thing that confuses matters is that as sugar is a solid (at normal temperatures) asking "what is the boiling point of sugar?" is like asking "what is the boiling point of ice?" It kind of makes sense but jars slightly.
Title: Re: Arithmetic that makes you cringe
Post by: ElyDave on 29 November, 2018, 02:47:55 pm
I'm not sure of the right terminology, but it may be that solid sugar does sublimation, not boiling*:

https://en.wikipedia.org/wiki/Sublimation_(phase_transition)

*Of course it's more complicated than that - and this is all physics, not chemistry IMHO!

It doesn't sublime, that is going straight from solid to gas, like CO2 (Dry Ice), it's a lot more complicated than that.

Apart from the descent into caramel, which then bubbles, if you have low enough moisture the sugar pyrolises and generates methanol as a byproduct, which is of course extremely flammable.  This is why sugar mills regularly go kaboom.
Title: Re: Arithmetic that makes you cringe
Post by: mattc on 29 November, 2018, 02:53:23 pm
I am very much liking the phrase

the descent into caramel

It should be a film title, or perhaps An Audax ...
Title: Re: Arithmetic that makes you cringe
Post by: Torslanda on 29 November, 2018, 03:20:36 pm
The descent into Caramel should follow the struggle to Kirkstone and be cherished fondantly...
Title: Re: Arithmetic that makes you cringe
Post by: Torslanda on 29 November, 2018, 03:21:48 pm
...and the climb must involve ganache-ing of gears.





I'll stop now
Title: Re: Arithmetic that makes you cringe
Post by: ElyDave on 29 November, 2018, 04:56:41 pm
But the finish is a sweet relief, almost the icing on the cake.

IGMC
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 29 November, 2018, 05:05:46 pm
Now, leaving aside the fact that the question is nonsensical, since sugar doesn't have a boiling point as such, it really infuriated me that Alexa didn't specify the scale in her answer - I can't recall the exact figure quoted but I'm sure it must have been in Fahrenheit, which shouldn't be too surprising given that Alexa is Transpondian, but a) my old maths teacher would have given her a clout round the ear for such sloppiness, and b) it's the 21st feckin' century so use Celsius already. Anyway, I amused myself by imagining that Our Intrepid Baker guessed that Alexa was working in Kelvin and so put their sugar solution in the freezer to boil it...

Presumably Alexa allows the user to configure their preferred units, date formats, etc. like most other Babbage-engine user interfaces.

Also, if I was molishing an English-language TV advert for such a device, I might deliberately avoid specific units, so as to save half a second of expensive air time and avoid the need for different versions for different markets.
Title: Re: Arithmetic that makes you cringe
Post by: ian on 29 November, 2018, 05:45:39 pm
Alexa lets you choose her temperature and distance units. I don't think she offers Kelvin or parsecs* though.

And yes, she should have said sucrose will melt/decompose (depending on the water content, moisture is how you get inversion, that's really the difference between making caramel and golden syrup).

*yes, yes, I know, but Han Solo is always going to be more right than you, so give it up.
Title: Re: Arithmetic that makes you cringe
Post by: ElyDave on 29 November, 2018, 06:16:39 pm
Alexa lets you choose her temperature and distance units. I don't think she offers Kelvin or parsecs* though.

And yes, she should have said sucrose will melt/decompose (depending on the water content, moisture is how you get inversion, that's really the difference between making caramel and golden syrup).

*yes, yes, I know, but Han Solo is always going to be more right than you, so give it up.

invert sugar syrup also needs an acid to do the "inversion".  I'm not sure if golden syrup is inverted or not?
Title: Re: Arithmetic that makes you cringe
Post by: ian on 29 November, 2018, 06:20:38 pm
Golden syrup is partially inverted.

You don't strictly need acid (water will donate the protons), though it'll speed up the hydrolysis.
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 29 November, 2018, 06:58:10 pm
Alexa lets you choose her temperature and distance units. I don't think she offers Kelvin or parsecs* though.

And yes, she should have said sucrose will melt/decompose (depending on the water content, moisture is how you get inversion, that's really the difference between making caramel and golden syrup).

*yes, yes, I know, but Han Solo is always going to be more right than you, so give it up.

invert sugar syrup also needs an acid to do the "inversion".  I'm not sure if golden syrup is inverted or not?

'Partially inverted refiners' syrup' if I recall the inscription on the Lyle's Golden Syrup correctly... ie a mixture of glucose, fructose & sucrose.
Title: Re: Arithmetic that makes you cringe
Post by: citoyen on 30 November, 2018, 07:34:46 am
*yes, yes, I know, but Han Solo is always going to be more right than you, so give it up.

“Han Solo is dead.” - Nietzsche
Title: Re: Arithmetic that makes you cringe
Post by: ian on 30 November, 2018, 09:39:13 am
Yes, and he's dead right.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 30 November, 2018, 09:55:47 am
Sugar is right, golden syrup is wrong, honey lives forever.
Title: Re: Arithmetic that makes you cringe
Post by: Greenbank on 30 November, 2018, 10:57:10 am
Forgot to ask Alexa the question this morning to see what it says, will ask this evening when back home.
Title: Re: Arithmetic that makes you cringe
Post by: ElyDave on 01 December, 2018, 06:47:12 am
Siri was surprisingly correct on this, vs it's usual ability to understand English

It directed me to a site that quite correctly pointed out that sugar does not boild but decomposes and caremelises, and refers to varying boiling point of syrups.

I may be being lulled into a false sense of security with Siri, heading for another disappointment
Title: Re: Arithmetic that makes you cringe
Post by: phantasmagoriana on 01 December, 2018, 07:08:52 am
Anyone who watched the last series of Bake Off will have seen the little Amazon Alexa ads that bookended each commercial break. One of them had Our Intrepid Baker asking "Alexa, what's the boiling point of sugar?" to which Alexa replies "The boiling point of sugar is XXX degrees."

Now, leaving aside the fact that the question is nonsensical, since sugar doesn't have a boiling point as such, it really infuriated me that Alexa didn't specify the scale in her answer - I can't recall the exact figure quoted but I'm sure it must have been in Fahrenheit, which shouldn't be too surprising given that Alexa is Transpondian, but a) my old maths teacher would have given her a clout round the ear for such sloppiness, and b) it's the 21st feckin' century so use Celsius already. Anyway, I amused myself by imagining that Our Intrepid Baker guessed that Alexa was working in Kelvin and so put their sugar solution in the freezer to boil it...

I just tried this - Alexa told me it was 160° Celsius.
Title: Re: Arithmetic that makes you cringe
Post by: Pingu on 08 January, 2019, 07:28:27 pm
‘Super-Earth’ among trio of planets and six supernovae detected by Tess mission (https://www.theguardian.com/science/2019/jan/08/nasa-spacecraft-planet-earth-tess-mission)

Quote
Three new planets and six supernovae outside our solar system have been observed by Nasa’s planet-hunting Tess mission in its first three months.

Well TFFT  ::-)
Title: Re: Arithmetic that makes you cringe
Post by: Pingu on 25 January, 2019, 10:08:35 pm
BBC science (https://www.bbc.co.uk/news/science-environment-47000888) bitches.

(https://farm8.staticflickr.com/7923/46875543641_c1b42faec1_z.jpg) (https://flic.kr/p/2eqeq1i)
bbc_science (https://flic.kr/p/2eqeq1i) by The Pingus (https://www.flickr.com/photos/the_pingus/), on Flickr
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 20 February, 2019, 04:36:33 pm
Since when was it 25 years from 1984 to 2018?

https://www.bbc.co.uk/news/uk-england-beds-bucks-herts-47309945 (https://www.bbc.co.uk/news/uk-england-beds-bucks-herts-47309945)
Title: Re: Arithmetic that makes you cringe
Post by: ElyDave on 20 February, 2019, 07:31:19 pm
even 1998 when he was released to 2018 isn't 25 years
Title: Re: Arithmetic that makes you cringe
Post by: Guy on 04 March, 2019, 03:19:59 pm
The Daily Hate online has a picture article about WW2 fortifications. One of the captions starts

Quote
These two pictures show parts of a 1km (1.5 mile)-long anti-tank wall..

 :facepalm:
Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 07 March, 2019, 12:24:22 pm
My own fault I guess for listening to "You and Your Things and Your Paranoia Yours".  However, they're just running an article about John Lewis and the bonus being paid this year. Apparently it's the lowest since 1953 at "Just 3%", while in the past it's been up as high   "as 20%".  3% of what wasn't disclosed though.  Gah.
Title: Re: Arithmetic that makes you cringe
Post by: jsabine on 07 March, 2019, 01:26:46 pm
3% of the recipient's annual salary.

They were clear enough about that on the news earlier, so maybe they just assume that anyone listening to Y&Y has had the Home Service on all day and will have absorbed these facts by osmosis.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 11 April, 2019, 10:16:38 am
Bataan regularly delivered; all four of his first five albums – Subway Joe (1968), Riot (1968), Poor Boy (1969) and Mr New York and The East Side Kids (1971) – were unambiguously about El Barrio, carrying images of the ghetto or everyday street life in New York.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 04 June, 2019, 02:46:14 am
I think this one is probably "Arithmetic that is too subtle for me." It's from a presentation of a medical trial. No one picked the presenter up on it, so I guess it makes sense to them.
Quote
There are four different domains: there is a bulbar domain, fine motor, gross motor and breathing, and all of these are scored 0 to 4, where 4 is normal function. So you have a maximum score of 48, which would be a normal person.
How is the maximum score 48 rather than 16?
Title: Re: Arithmetic that makes you cringe
Post by: ElyDave on 04 June, 2019, 05:53:50 am
being added to something else they forgotbtontell you about?

not so much makes me cringe, but one that played with my head recently. Zero factorial = 1.
the set-theory explanation makes sense, but the numerical solution I read was a fudge.
Title: Re: Arithmetic that makes you cringe
Post by: Manotea on 04 June, 2019, 07:28:42 am
The thing to remember is that half the people you meet are below average.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 04 June, 2019, 07:34:08 am
being added to something else they forgotbtontell you about?

not so much makes me cringe, but one that played with my head recently. Zero factorial = 1.
the set-theory explanation makes sense, but the numerical solution I read was a fudge.

This one doesn't seem too sweet to be wholesome: https://youtu.be/Mfk_L4Nx2ZI

The thing to remember is that half the people you meet are below average.

Top half or bottom half?
Title: Re: Arithmetic that makes you cringe
Post by: Beardy on 04 June, 2019, 09:25:59 am
The thing to remember is that half the people you meet are below average.
That largley depends on which average you are using.
Title: Re: Arithmetic that makes you cringe
Post by: Manotea on 04 June, 2019, 07:17:36 pm
Mrs F was never that much into Numbers and all.
She had to do a Tax module at Law School back in the day.

I remember trying to help out with the basic problem:

If something costs £100, and we add 10% tax, it then costs £110. That's fine.
But why can't I just remove the tax element by removing 10% of the £110?

She's still not convinced about the arithmetic, and suspects alien involvement.

I still find it working that if a share falls by 33%, say from 1.50 to 1, it needs to increase my by 50% to get back to where it was....
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 30 September, 2019, 10:12:09 am
The thing to remember is that half the people you meet are below average.
That largley depends on which average you are using.
Central limit theorem says that it doesn't matter whether you use mean, median or (grouped) mode, Manotea is right.

In other news
https://www.bbc.co.uk/news/world-asia-china-49874969 (https://www.bbc.co.uk/news/world-asia-china-49874969)
2 square metres is not 6.6 square feet...  The fact that they've tried to show the equivalence makes me think it was (2 metres) squared, which is 4 square metres, or 43 square feet.
Title: Re: Arithmetic that makes you cringe
Post by: Jaded on 30 September, 2019, 11:18:06 am
Surely 2 sq mtrs is 22 sq ft.

2 mtr sq is 43 sq ft.
Title: Re: Arithmetic that makes you cringe
Post by: tatanab on 30 September, 2019, 11:48:35 am
Quote
The fact that they've tried to show the equivalence makes me think it was (2 metres) squared, which is 4 square metres, or 43 square feet.
That in itself leads to misunderstandings.  it is not 2 metres squared but 2 metres square which means it is a square with 2 metre sides.  I noticed this modern use of squared in one of those fly on the wall school programmes.   In the answer to a question, little Johnny replied "2 metres squared" when the correct answer would have been "2 square metres".  Little Johnny thought the 2 always meant squared.  Of course the teacher did not correct him.  Lets hope he never becomes a carpet fitter.
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 30 September, 2019, 11:52:54 am
Yeah, I think what they're trying to suggest (though the unclear photo does little to corroborate this) is that the space is (2m)x(2m) or (6'7")x(6'7").
You're absolutely right that 2m2 is 22 sq ft.
Title: Re: Arithmetic that makes you cringe
Post by: Phil W on 30 September, 2019, 12:32:36 pm
Quote
The fact that they've tried to show the equivalence makes me think it was (2 metres) squared, which is 4 square metres, or 43 square feet.
That in itself leads to misunderstandings.  it is not 2 metres squared but 2 metres square which means it is a square with 2 metre sides.  I noticed this modern use of squared in one of those fly on the wall school programmes.   In the answer to a question, little Johnny replied "2 metres squared" when the correct answer would have been "2 square metres".  Little Johnny thought the 2 always meant squared.  Of course the teacher did not correct him.  Lets hope he never becomes a carpet fitter.

The teacher may well become a carpet fitter.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 30 September, 2019, 01:00:04 pm
Quote
The fact that they've tried to show the equivalence makes me think it was (2 metres) squared, which is 4 square metres, or 43 square feet.
That in itself leads to misunderstandings.  it is not 2 metres squared but 2 metres square which means it is a square with 2 metre sides.  I noticed this modern use of squared in one of those fly on the wall school programmes.   In the answer to a question, little Johnny replied "2 metres squared" when the correct answer would have been "2 square metres".  Little Johnny thought the 2 always meant squared.  Of course the teacher did not correct him.  Lets hope he never becomes a carpet fitter.

The confusion probably comes from reading 2 m² as if m is a variable - we say a² as "a squared" rather than "square a's".
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 30 September, 2019, 01:46:05 pm
The confusion probably comes from reading 2 m² as if m is a variable - we say a² as "a squared" rather than "square a's".

I don't actually think that's confusing, unless you read it out:  BODMAS[1] requires that you square the metre (to get square metres), then multiply by 2.

Doing maths on the units is normal and ordinary in physics, so there's nothing particularly special about length and area.  Unless your maths education stops at carpet-fitting 101, I suppose.


[1] Other mnemonics are available.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 30 September, 2019, 03:30:36 pm
It's a reasonable mistake for a child to make, though. Not so forgivable for an adult, even if they do work for the Beeb - although I believe there are people who go into denial of maths once they leave school.

Reminds me for some reason of a candidate I once interviewed for a place as programming intern: I asked her what programming languages she had studied so far and she replied "I don't know, I wasn't paying attention".
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 30 September, 2019, 04:02:27 pm
Reminds me for some reason of a candidate I once interviewed for a place as programming intern: I asked her what programming languages she had studied so far and she replied "I don't know, I wasn't paying attention".

I think I remember offering to help her with some Java coursework.  When asked what it was she didn't understand, the answer was "Well, Java".
Title: Re: Arithmetic that makes you cringe
Post by: essexian on 30 September, 2019, 04:40:48 pm
Did anyone see: "Who wants to be a millionaire" a couple of weeks back? One of the questions was something like: What answer do you get if you add 9+8+7+6+5+4+3+2+1?  The answers given were something like: 40, 42, 45 or 48.

Yes, they (a teacher if I remember) got it wrong.  :facepalm:
Title: Re: Arithmetic that makes you cringe
Post by: caerau on 30 September, 2019, 05:20:08 pm
Did anyone see: "Who wants to be a millionaire" a couple of weeks back? One of the questions was something like: What answer do you get if you add 9+8+7+6+5+4+3+2+1?  The answers given were something like: 40, 42, 45 or 48.

Yes, they (a teacher if I remember) got it wrong.  :facepalm:


Yes that was cringeworthy - to a point - she could have taken more time - but under that pressure in front of the cameras... easily done.  There but the grace of bod...
Title: Re: Arithmetic that makes you cringe
Post by: ian on 30 September, 2019, 06:09:22 pm
Quote
The fact that they've tried to show the equivalence makes me think it was (2 metres) squared, which is 4 square metres, or 43 square feet.
That in itself leads to misunderstandings.  it is not 2 metres squared but 2 metres square which means it is a square with 2 metre sides.  I noticed this modern use of squared in one of those fly on the wall school programmes.   In the answer to a question, little Johnny replied "2 metres squared" when the correct answer would have been "2 square metres".  Little Johnny thought the 2 always meant squared.  Of course the teacher did not correct him.  Lets hope he never becomes a carpet fitter.

To be fair, as a scientist, I was puzzled to find that umpteen square metres of promised paint cover did not turn out to be as anticipated.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 01 October, 2019, 10:09:47 am
The public toilets have been closed for a couple of years. If you can't have a pee, have a pi!
https://www.bristol247.com/news-and-features/news/mathematical-graffiti-in-the-bearpit/
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 01 October, 2019, 12:03:08 pm
Quote
The fact that they've tried to show the equivalence makes me think it was (2 metres) squared, which is 4 square metres, or 43 square feet.
That in itself leads to misunderstandings.  it is not 2 metres squared but 2 metres square which means it is a square with 2 metre sides.  I noticed this modern use of squared in one of those fly on the wall school programmes.   In the answer to a question, little Johnny replied "2 metres squared" when the correct answer would have been "2 square metres".  Little Johnny thought the 2 always meant squared.  Of course the teacher did not correct him.  Lets hope he never becomes a carpet fitter.

To be fair, as a scientist, I was puzzled to find that umpteen square metres of promised paint cover did not turn out to be as anticipated.

To be fair, paint-manufacturer square metres are a bit like tent-manufacturer persons.
Title: Re: Arithmetic that makes you cringe
Post by: pcolbeck on 01 October, 2019, 12:09:38 pm
To be fair, paint-manufacturer square metres are a bit like tent-manufacturer persons.

Since a tent manufacturers designated four man tent is usually only suitable for three people, a three for two and a two for one I often wonder who their one man tents are designed for ....
Title: Re: Arithmetic that makes you cringe
Post by: arabella on 01 October, 2019, 07:40:49 pm
For me!
and other persons of sensible size.

If only I could find the corresponding sleeping bag rather than one made for a 6' plus user.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 01 October, 2019, 07:48:00 pm
When SmallestCub was a bit smaller than he is now[1], we decided that we could both fit in my Akto.


[1] Though not small enough to use that Jiffy bag as a sleeping bag any more.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 01 October, 2019, 07:57:01 pm
I'd have said it was a bit different. A 1-person tent is the right size for 1.2 persons, a 2-person for 1.8, a 3-person for 2.6 and similar.
Title: Re: Arithmetic that makes you cringe
Post by: Jasmine on 02 October, 2019, 08:47:58 am
Quote
The fact that they've tried to show the equivalence makes me think it was (2 metres) squared, which is 4 square metres, or 43 square feet.
That in itself leads to misunderstandings.  it is not 2 metres squared but 2 metres square which means it is a square with 2 metre sides.  I noticed this modern use of squared in one of those fly on the wall school programmes.   In the answer to a question, little Johnny replied "2 metres squared" when the correct answer would have been "2 square metres".  Little Johnny thought the 2 always meant squared.  Of course the teacher did not correct him.  Lets hope he never becomes a carpet fitter.

It's quite likely that the teacher doesn't know the difference either. As Kim says, it's becomes an issue when read out loud. However, it also becomes an issue when people start to think that 2m2 is the same as (2m)2. A few years ago I was invited to presentations from Masters level students on Environmental Impact Assessment (EIA) projects. My general feedback at the end of the session was that at least 3/4 of the presentations were using the phrase xxx metres squared, when they meant xxx square metres. Using it as a mental shorthand is one thing, but telling the regulator that there will be loss of an important habitat of 100 square metres when you meant 10 square metres because you've said "10 metres, squared" could be the difference between the project being permissible or not.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 02 October, 2019, 09:14:01 am
I've always thought of 2m2 as 2 square metres and a space 2m x 2m as a 2-metre square. Perhaps it would be clearer if we used a distinct term for area, so 2m2 would be 2 centiares.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 02 October, 2019, 09:15:29 am
Small wonder that the newspapers talk in football pitches, esp when the Gardyloo uses a US reporter and replaces field by pitch but doesn't change the figure.

Disclaimer: I haven't the foggiest idea how big a football pitch (or field) is. Several thousand square elephants, I should think.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 02 October, 2019, 09:17:27 am
I've always thought of 2m2 as 2 square metres and a space 2m x 2m as a 2-metre square. Perhaps it would be clearer if we used a distinct term for area, so 2m2 would be 2 centiares.

Centiares?  Not even in France, where people already talk in ares, have I heard that term.

Any relation of Nessus?
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 02 October, 2019, 09:17:38 am
Confused by hectares? You will be after reading this!
https://www.linkedin.com/pulse/understanding-land-sizes-measurement-ann-nwaukwa
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 02 October, 2019, 09:19:08 am
Don't think I'll bother.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 02 October, 2019, 09:19:22 am
I've always thought of 2m2 as 2 square metres and a space 2m x 2m as a 2-metre square. Perhaps it would be clearer if we used a distinct term for area, so 2m2 would be 2 centiares.

Centiares?  Not even in France, where people already talk in ares, have I heard that term.

Any relation of Nessus?
No, that's the point. It's not a term in use but it might avoid confusion between square metres, metres squared and metre squares.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 02 October, 2019, 09:38:15 am
Teach the buggers properly to start with would work better than introducing unfamiliar terms and expecting them to remember.

I reckon that a lot of the confusion in the media results from reporters having learnt the terms at school but forgotten them for lack of use.  I learnt physics in CGS units and was aware of MKS, but when SI arrived and everything got called after dead'uns I sort-of tuned out.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 02 October, 2019, 09:50:52 am
Wikipedia tells me CGS = centimetre, gram, second and MKS = metre, kilogram, second. To my mind these are the same system, just at different scales. Isn't half the point of metric/SI that it's easy to relate between different scales because everything goes up and down in 10s, rather than an assortment of 12s, 16s, 20s and whatever in Imperial (and various other pre-metric systems)?
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 02 October, 2019, 01:11:03 pm
I've got a container of industrial-strength glyphosate - gardening, for the use of.  The destructions specify dilutions in millilitres per hectare[1].  Interestingly this manages to make the chemistry and the maths equally scary.


[1] Fairly sure that's nanometres...
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 02 October, 2019, 01:41:43 pm
No, you'd be putting 10 times too much on!

1ml = 10-6m3
1ha = 104m2
1ml/ha = 10-6/104m = 10-10m = 1 ångström

Mind you, my experience of applying agri-death is that it's nigh-impossible to spray anything like evenly.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 02 October, 2019, 02:56:52 pm
Financial analyst: What are the prospects for Product X?
Big boss: Product X sells £3.2 million, which is 8% of total sales. We have the capacity to increase that to 15%.
FA: Okay... my maths isn't that great.
BB: Alright, we can basically almost double it.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 02 October, 2019, 03:26:26 pm
Wikipedia tells me CGS = centimetre, gram, second and MKS = metre, kilogram, second. To my mind these are the same system, just at different scales. Isn't half the point of metric/SI that it's easy to relate between different scales because everything goes up and down in 10s, rather than an assortment of 12s, 16s, 20s and whatever in Imperial (and various other pre-metric systems)?

The danger with metric-based systems is losing track of the decimal point.  I did this during my A-level physics practical and the invigilator, who was wandering round making sure nobody was using a crafty AVOmeter, glanced at my pad and murmured "you might want to check that" as he passed my bench.
Title: Re: Arithmetic that makes you cringe
Post by: fuaran on 02 October, 2019, 03:49:58 pm
Financial analyst: What are the prospects for Product X?
Big boss: Product X sells £3.2 million, which is 8% of total sales. We have the capacity to increase that to 15%.
FA: Okay... my maths isn't that great.
BB: Alright, we can basically almost double it.
Depends on whether the total sales stay the same, or increase, or decrease...
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 02 October, 2019, 03:57:10 pm
The danger with metric-based systems is losing track of the decimal point.  I did this during my A-level physics practical and the invigilator, who was wandering round making sure nobody was using a crafty AVOmeter, glanced at my pad and murmured "you might want to check that" as he passed my bench.
Indeed.  We (structural engineers) measure on site to mm, but work out loads in kN/m2 or kN/m.  Steel section serial sizes are related to the dimension in mm, but the tables of section properties quote Z in cm3 and I in cm4 (zenzizenzic centimetres, FYI).  Yield strengths of steels are quoted in MPa (N/mm2 or 103kN/m2).  Young's modulus is quoted in GPa (kN/mm2).
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 02 October, 2019, 04:20:59 pm
Financial analyst: What are the prospects for Product X?
Big boss: Product X sells £3.2 million, which is 8% of total sales. We have the capacity to increase that to 15%.
FA: Okay... my maths isn't that great.
BB: Alright, we can basically almost double it.
Depends on whether the total sales stay the same, or increase, or decrease...
Not really. The question was about capacity not potential sales. The FA simply had to realize that 15 is approximately double 8.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 16 December, 2019, 11:49:49 am
Quote
Across the Bristol area, roughly three in four people over the age of 18 voted in the General Election. Across the country, it was fewer than two in three.

Nationally, turnout in the 2019 election was 67.2 per cent - down 1.6 per cent on the poll in 2017.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 17 December, 2019, 08:56:58 am
Quote
Across the Bristol area, roughly three in four people over the age of 18 voted in the General Election. Across the country, it was fewer than two in three.

Nationally, turnout in the 2019 election was 67.2 per cent - down 1.6 per cent on the poll in 2017.
So, fewer means either one or none.
Also, the bit "roughly three in four people over the age of 18 voted" seems to be either redundant or leaves me wondering about the proportion of under-18 voters.
Title: Re: Arithmetic that makes you cringe
Post by: Moleman76 on 18 December, 2019, 07:54:26 am
Also, the bit "roughly three in four people over the age of 18 voted" seems to be either redundant or leaves me wondering about the proportion of under-18 voters.
Mr. Drumpf would say they were the Hillary voters.

Would it be clearer to say "roughly three in four people of voting age voted" ?
Title: Re: Arithmetic that makes you cringe
Post by: ElyDave on 18 December, 2019, 09:07:30 am
surely the easiest way would be to say 2sq.m and 2m2 to avoid confusion?  Happens regularly in my industry - both the designations and confusion
Title: Re: Arithmetic that makes you cringe
Post by: ian on 18 December, 2019, 09:17:39 am
Also, the bit "roughly three in four people over the age of 18 voted" seems to be either redundant or leaves me wondering about the proportion of under-18 voters.
Mr. Drumpf would say they were the Hillary voters.

Would it be clearer to say "roughly three in four people of voting age voted" ?

Why not just three quarters in Bristol compared with two-thirds across the country. When did fractions become so vulgar?
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 18 December, 2019, 09:27:54 am
Quote
Across the Bristol area, roughly three in four people over the age of 18 voted in the General Election. Across the country, it was fewer than two in three.

Nationally, turnout in the 2019 election was 67.2 per cent - down 1.6 per cent on the poll in 2017.
So, fewer means either one or none.
Also, the bit "roughly three in four people over the age of 18 voted" seems to be either redundant or leaves me wondering about the proportion of under-18 voters.
Good point about fewer, but if that were the problem, it would be in the Grammar thread. All I noticed is that 67.2% is more than two in three.
Title: Re: Arithmetic that makes you cringe
Post by: hatler on 16 January, 2020, 11:26:50 pm
Quote
Kashmir covers around 86,000 sq miles (138 sq km), and is famed for the beauty of its lakes, meadows and snow-capped mountains.

From https://www.bbc.co.uk/news/world-asia-51131294
Title: Re: Arithmetic that makes you cringe
Post by: Ben T on 16 January, 2020, 11:45:44 pm
If you order something that's basically a closed flexible band, that's to go round something round, and it's described as having "diameter: 4cm".
When you get it, you lay it flat on a surface (so it's doubled up) and measure it. 4cm.
IS that it's diameter?? Cos to me, that's half the circumference.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 27 January, 2020, 09:39:45 am
Monday puzzle in that there Grauniad:
Quote
Here’s another numerical palindrome:

50, 20, 10, 01, 02, 05

It’s the pence value of the UK coins in circulation under a pound.

What is the highest value of UK coins you can have in your pocket without being able to exchange them exactly for a £10 note?

(This puzzle is filed under. ‘Not difficult but you’d be surprised at how many people get it wrong.’)
I don't get this. How could the answer possibly not be £9.99? But there must be something else cos that's just too obvious. Does he mean only using each value of coin once? Or what? It feels like there's some assumption that's so obvious he hasn't stated it but I'm missing it.
Title: Re: Arithmetic that makes you cringe
Post by: nicknack on 27 January, 2020, 10:17:11 am
Monday puzzle in that there Grauniad:
Quote
Here’s another numerical palindrome:

50, 20, 10, 01, 02, 05

It’s the pence value of the UK coins in circulation under a pound.

What is the highest value of UK coins you can have in your pocket without being able to exchange them exactly for a £10 note?

(This puzzle is filed under. ‘Not difficult but you’d be surprised at how many people get it wrong.’)
I don't get this. How could the answer possibly not be £9.99? But there must be something else cos that's just too obvious. Does he mean only using each value of coin once? Or what? It feels like there's some assumption that's so obvious he hasn't stated it but I'm missing it.
Dunno what the actual answer is, but if you had a 19x50s and 3x20s then you'd have £10.10 which is more than £9.99.
<thinks>
Or 49x20s and 1x50 = £10.30
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 27 January, 2020, 10:19:02 am
My interpretation is

Quote
What is the highest value of UK coins you can have in your pocket without being able to exchange some of them exactly for a £10 note?

If you had 49no 20pences and 1no 50pence, you'd have £10.30, but wouldn't be able to make £10.  I think this is the solution.

See also: 43 Chicken McNuggets

Edit: cross-posted with nicknack!
Title: Re: Arithmetic that makes you cringe
Post by: Phil W on 27 January, 2020, 10:47:14 am
You could also add 5p and 2 x 2p to that and still not be able to make up £10, so £10.39
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 27 January, 2020, 11:17:24 am
Good spot!
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 27 January, 2020, 11:23:16 am
My interpretation is

Quote
What is the highest value of UK coins you can have in your pocket without being able to exchange some of them exactly for a £10 note?

If you had 49no 20pences and 1no 50pence, you'd have £10.30, but wouldn't be able to make £10.  I think this is the solution.
Okay, that makes sense. And Nicknack's answer, which has the advantage of being almost palindromic.

Quote
See also: 43 Chicken McNuggets
What?  ???
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 27 January, 2020, 12:40:39 pm
43 is the largest number of Chicken McNuggets which couldn't be made using the standard sized packs (6, 9, 20).
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 27 January, 2020, 02:15:21 pm
43 is the largest number of Chicken McNuggets which couldn't be made using the standard sized packs (6, 9, 20).
This is why McDonalds have their own university!
Title: Re: Arithmetic that makes you cringe
Post by: Wowbagger on 27 January, 2020, 02:22:22 pm
43 is the largest number of Chicken McNuggets which couldn't be made using the standard sized packs (6, 9, 20).

This reminds me of a rather neat problem I recall from my primary school teaching days.

A 40kg weight drops on the floor and breaks into 4 pieces. It so happens that the pieces are precisely the correct mass to allow any number of whole kilograms from 1 to 40 to be weighed on a balance. What is the mass of each of the 4 pieces?
Title: Re: Arithmetic that makes you cringe
Post by: rr on 27 January, 2020, 04:15:40 pm
You could also add 5p and 2 x 2p to that and still not be able to make up £10, so £10.39
Can't you have 4×2p, making £10.43?

Sent from my moto x4 using Tapatalk

Title: Re: Arithmetic that makes you cringe
Post by: rr on 27 January, 2020, 05:27:08 pm
You could also add 5p and 2 x 2p to that and still not be able to make up £10, so £10.39
Can't you have 4×2p, making £10.43?

Sent from my moto x4 using Tapatalk
Indeed you can, the answer is £10.43

Sent from my moto x4 using Tapatalk

Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 30 January, 2020, 07:51:29 am
43 is the largest number of Chicken McNuggets which couldn't be made using the standard sized packs (6, 9, 20).

This reminds me of a rather neat problem I recall from my primary school teaching days.

A 40kg weight drops on the floor and breaks into 4 pieces. It so happens that the pieces are precisely the correct mass to allow any number of whole kilograms from 1 to 40 to be weighed on a balance. What is the mass of each of the 4 pieces?
I've been chewing this over while fooling up and down the motorways of this fair land.
A series of (2^n)-1 sort of works, in that, for example pieces with masses of 1,3 , 7 and 15 kg allow you to get any of 1 to 26kg (I think). However it fails on the totalling 40kg front.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 30 January, 2020, 08:40:53 am
'Reduces the temperature by 20%' using deg. F - that could get tricky. OK if R or K used.
Title: Re: Arithmetic that makes you cringe
Post by: Wowbagger on 30 January, 2020, 09:40:14 am
43 is the largest number of Chicken McNuggets which couldn't be made using the standard sized packs (6, 9, 20).

This reminds me of a rather neat problem I recall from my primary school teaching days.

A 40kg weight drops on the floor and breaks into 4 pieces. It so happens that the pieces are precisely the correct mass to allow any number of whole kilograms from 1 to 40 to be weighed on a balance. What is the mass of each of the 4 pieces?
I've been chewing this over while fooling up and down the motorways of this fair land.
A series of (2^n)-1 sort of works, in that, for example pieces with masses of 1,3 , 7 and 15 kg allow you to get any of 1 to 26kg (I think). However it fails on the totalling 40kg front.

1 & 3 are correct. However, 7 is unnecessarily small as it allows 2 ways of reaching 4 (3+1 and 7-3)...
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 30 January, 2020, 10:59:50 am
It's 3^n.

1, 3, 9, 27 work.
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 30 January, 2020, 11:08:22 am
It's not really 'arithmetic that makes you cringe' but this is a nice problem nonetheless...

There are 1000 numbered lockers in a line.  All of them are closed.
First, you pass along the line, changing the door position (i.e. opening!) every door.
Then, you go back to the start, changing the door position (i.e. closing) every even-numbered door.
Then you go back to the start, changing the door position of every third door (i.e. closing door 3, opening door 6, closing door 9...).
Then you go back to the start, changing the door position of every fourth door.
Then every fifth door.
...
... Lastly, change the door position of door 1000.

How many doors are open, and how many are closed?
Title: Re: Arithmetic that makes you cringe
Post by: Wowbagger on 30 January, 2020, 11:10:31 am
It's 3^n.

1, 3, 9, 27 work.

Correct!
Title: Re: Arithmetic that makes you cringe
Post by: Greenbank on 30 January, 2020, 11:29:03 am
How many doors are open, and how many are closed?

Ah yes, I remember this one.

(click to show/hide)
Title: Re: Arithmetic that makes you cringe
Post by: Wowbagger on 30 January, 2020, 11:42:51 am
Yes, of course. They are the only numbers that have an odd number of factors.
Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 30 January, 2020, 12:08:03 pm
It's not really 'arithmetic that makes you cringe' but this is a nice problem nonetheless...

There are 1000 numbered lockers in a line.  All of them are closed.
First, you pass along the line, changing the door position (i.e. opening!) every door.
Then, you go back to the start, changing the door position (i.e. closing) every even-numbered door.
Then you go back to the start, changing the door position of every third door (i.e. closing door 3, opening door 6, closing door 9...).
Then you go back to the start, changing the door position of every fourth door.
Then every fifth door.
...
... Lastly, change the door position of door 1000.

How many doors are open, and how many are closed?
These lockers. Are they in the cloakroom at Hilbert's hotel?
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 30 January, 2020, 01:28:45 pm
Hehe!

Another lovely problem:

A man is in a rowing boat in the middle of a pond.  He takes a large rock from the bottom of the boat and drops it into the water, whereupon it sinks.  What happens to the level of the water in the pond?
Title: Re: Arithmetic that makes you cringe
Post by: tonyh on 30 January, 2020, 01:39:53 pm
Same volume of water displaced whether the rock is on the bottom or in the boat, so no change?
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 30 January, 2020, 01:43:05 pm
Surely the displacement required to support the rock is greater than the volume of the rock, as it's more dense than water.  On that basis, the water level goes down?
Title: Re: Arithmetic that makes you cringe
Post by: tonyh on 30 January, 2020, 01:49:01 pm
That looks MUCH better!
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 30 January, 2020, 03:34:32 pm
Kim has it.  It's a little counterintuitive!
Title: Re: Arithmetic that makes you cringe
Post by: tonyh on 30 January, 2020, 03:38:31 pm
Thanks, Legs. Yes, a lovely problem.

Brain now updated (I hope).
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 03 February, 2020, 04:15:41 pm
This image of Gerald Corrigan's house shows where North Wales Police believe the shooter was located (https://www.bbc.co.uk/news/uk-wales-51360832)
(https://ichef.bbci.co.uk/news/624/cpsprodpb/D2B3/production/_110693935_crossbow.png)

A triumph of precision over accuracy.
Title: Re: Arithmetic that makes you cringe
Post by: Basil on 03 February, 2020, 07:32:40 pm
I was expecting that would convert to a nice round number of feet or yards.  But it doesn't. 
That's the usual reason for decimals of that precision in press reports.

So, we can expect a cow to be arrested some time soon.
Title: Re: Arithmetic that makes you cringe
Post by: Wowbagger on 03 February, 2020, 07:36:57 pm
This image of Gerald Corrigan's house shows where North Wales Police believe the shooter was located (https://www.bbc.co.uk/news/uk-wales-51360832)
(https://ichef.bbci.co.uk/news/624/cpsprodpb/D2B3/production/_110693935_crossbow.png)

A triumph of precision over accuracy.
[/quote

Was that the case of the bloke who got shot by someone with a crossbow?
Title: Re: Arithmetic that makes you cringe
Post by: Phil W on 03 February, 2020, 07:48:30 pm
Hehe!

Another lovely problem:

A man is in a rowing boat in the middle of a pond.  He takes a large rock from the bottom of the boat and drops it into the water, whereupon it sinks.  What happens to the level of the water in the pond?

The large rock penetrates the pond lining and completely empties it of water, leaving the man and boat on a muddy slimy bottom.
Title: Re: Arithmetic that makes you cringe
Post by: tatanab on 03 February, 2020, 08:05:58 pm
^^^^^^^^^ I was asked that question in interview with Vosper Thorneycroft back when the world was young (about 1987).  The difference was that it was a large ship, a very small very heavy weight, and a dockyard basin.  A question in logical thinking.  They are probably not allowed to ask things like that these days.
Title: Re: Arithmetic that makes you cringe
Post by: pcolbeck on 14 February, 2020, 12:34:06 pm
Surely the displacement required to support the rock is greater than the volume of the rock, as it's more dense than water.  On that basis, the water level goes down?

Your right I think. The size of the rock is immaterial to the displacement needed by the boat to support but it its weight is.  An empty steel box 1m3 would displace much less than a box the same size filled with something really dense like lead or gold. Drop them in the water and they both displace 1m3 of water no matter what their weight is. When its on the boat its a weight problem when its in the water its a volume problem.
Title: Re: Arithmetic that makes you cringe
Post by: Pingu on 28 June, 2020, 11:16:36 pm
The redundancy of 'x by x square'.
Title: Re: Arithmetic that makes you cringe
Post by: Pingu on 03 July, 2020, 05:47:59 pm
Hmm...

Quote from: grauniad
The existing major satellite navigational systems all use satellites orbiting about 20km from the Earth’s surface, compared with only 1.2km for low-Earth orbits.

https://www.theguardian.com/business/2020/jul/03/uk-buys-stake-bankrupt-oneweb-satellite-rival-eu-galileo-system
Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 03 July, 2020, 06:14:04 pm
Hmm...

Quote from: grauniad
The existing major satellite navigational systems all use satellites orbiting about 20km from the Earth’s surface, compared with only 1.2km for low-Earth orbits.

https://www.theguardian.com/business/2020/jul/03/uk-buys-stake-bankrupt-oneweb-satellite-rival-eu-galileo-system

Chortle!  I am now trying to picture satellites passing a thousand feet beneath Denver.

Edit: They've fixed it :(
Title: Re: Arithmetic that makes you cringe
Post by: spesh on 03 July, 2020, 06:45:31 pm
Hmm...

Quote from: grauniad
The existing major satellite navigational systems all use satellites orbiting about 20km from the Earth’s surface, compared with only 1.2km for low-Earth orbits.

https://www.theguardian.com/business/2020/jul/03/uk-buys-stake-bankrupt-oneweb-satellite-rival-eu-galileo-system

Chortle!  I am now trying to picture satellites passing a thousand feet beneath Denver.

That's what the ultra-SEEKRIT tunnels under Denver are for (the tunnels under the airport that we do know about were built as a distraction).  :demon: ;) :demon:

Quote
Edit: They've fixed it :(

Spoilsports.  ::-)
Title: Re: Arithmetic that makes you cringe
Post by: Asterix, the former Gaul. on 03 July, 2020, 08:27:27 pm
Hehe!

Another lovely problem:

A man is in a rowing boat in the middle of a pond.  He takes a large rock from the bottom of the boat and drops it into the water, whereupon it sinks.  What happens to the level of the water in the pond?

The large rock penetrates the pond lining and completely empties it of water, leaving the man and boat on a muddy slimy bottom.

In the last day or so our pond's water level started to drop consistently. We'd fill it up; hours later the level dropped.

We supposed there was a sudden leak - I'd been doing heavy gardening one side of it but I couldn't imagine how that would have damaged the lining.

Then I remembered we'd once had a fountain and the pipe was still there.  Yup, the gardening had displaced the loose pipe and it had started to syphon out the water.  I could put away the bicycle tyre repair kit.  No arithmetic I'm afraid. 
Title: Re: Arithmetic that makes you cringe
Post by: cygnet on 04 July, 2020, 05:01:06 am
Failing to understand the difference between m2 and meters square
https://www.ice.org.uk/what-is-civil-engineering/what-do-civil-engineers-do/post-office-tower (https://www.ice.org.uk/what-is-civil-engineering/what-do-civil-engineers-do/post-office-tower)
Quote from: ICE
The project team sank a concrete raft about 8m into the ground to deal with this. The 27m² raft was 1m thick and reinforced with 6 layers of cables.

Title: Re: Arithmetic that makes you cringe
Post by: tonyh on 04 July, 2020, 05:42:09 am
Yes.

And, is m2 better read as "square metres", "square metre", "metres squared", or "metre squared"?
Title: Re: Arithmetic that makes you cringe
Post by: ElyDave on 04 July, 2020, 07:55:47 am
As a professional sceptic, I always ask about units. I had a professional conversation with a bunch of Norwegians a few weeks ago in which they were so steeped in metric that they had no idea anything other than a 1000kg ton exists.

Oh how we laughed!
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 04 July, 2020, 08:32:48 am
Failing to understand the difference between m2 and meters square
https://www.ice.org.uk/what-is-civil-engineering/what-do-civil-engineers-do/post-office-tower (https://www.ice.org.uk/what-is-civil-engineering/what-do-civil-engineers-do/post-office-tower)
Quote from: ICE
The project team sank a concrete raft about 8m into the ground to deal with this. The 27m² raft was 1m thick and reinforced with 6 layers of cables.

A square with a side of 10 metres covers 100 square metres, or 100 m2.  An square that 100 metres on a side is 100 metres square and covers 10,000 m2.
Title: Re: Arithmetic that makes you cringe
Post by: Asterix, the former Gaul. on 04 July, 2020, 02:53:30 pm
As a professional sceptic, I always ask about units. I had a professional conversation with a bunch of Norwegians a few weeks ago in which they were so steeped in metric that they had no idea anything other than a 1000kg ton exists.

Oh how we laughed!

Does it?  We called 1000kg a tonne to avoid error.  But if you are talking about a ton do you mean a long ton a short ton?
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 04 July, 2020, 05:09:04 pm
And how about three-square files?
Title: Re: Arithmetic that makes you cringe
Post by: ElyDave on 04 July, 2020, 05:27:10 pm
As a professional sceptic, I always ask about units. I had a professional conversation with a bunch of Norwegians a few weeks ago in which they were so steeped in metric that they had no idea anything other than a 1000kg ton exists.

Oh how we laughed!

Does it?  We called 1000kg a tonne to avoid error.  But if you are talking about a ton do you mean a long ton a short ton?

that was kind of the point, and why I wrote it like that. The Norwegians were using ton when they meant tonne, but were unaware of the distinction,

I asked exactly the same question as you
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 04 July, 2020, 07:05:23 pm
English has the luxury of silent letters.
Title: Re: Arithmetic that makes you cringe
Post by: ian on 04 July, 2020, 09:37:52 pm
Square metres, that's why you always find scowling paint-spattered scientists in the checkout queue at B&Q with four more tubs of paint.
Title: Re: Arithmetic that makes you cringe
Post by: cygnet on 04 July, 2020, 10:45:42 pm
Failing to understand the difference between m2 and meters square
https://www.ice.org.uk/what-is-civil-engineering/what-do-civil-engineers-do/post-office-tower (https://www.ice.org.uk/what-is-civil-engineering/what-do-civil-engineers-do/post-office-tower)
Quote from: ICE
The project team sank a concrete raft about 8m into the ground to deal with this. The 27m² raft was 1m thick and reinforced with 6 layers of cables.

A square with a side of 10 metres covers 100 square metres, or 100 m2.  An square that 100 metres on a side is 100 metres square and covers 10,000 m2.

Yes. 27m2 == 5 and a bit metres x 5 and a bit. Which is f.all when you are building a 177m high tower to withstand a nuclear bomb dropped on parliament. BBC etc reportage is woefully inadequate at checking this sort of stuff but you might expect the Institution of Civil Engineers to understand the difference...
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 05 July, 2020, 09:37:07 am
Failing to understand the difference between m2 and meters square
https://www.ice.org.uk/what-is-civil-engineering/what-do-civil-engineers-do/post-office-tower (https://www.ice.org.uk/what-is-civil-engineering/what-do-civil-engineers-do/post-office-tower)
Quote from: ICE
The project team sank a concrete raft about 8m into the ground to deal with this. The 27m² raft was 1m thick and reinforced with 6 layers of cables.

A square with a side of 10 metres covers 100 square metres, or 100 m2.  An square that 100 metres on a side is 100 metres square and covers 10,000 m2.

Yes. 27m2 == 5 and a bit metres x 5 and a bit. Which is f.all when you are building a 177m high tower to withstand a nuclear bomb dropped on parliament. BBC etc reportage is woefully inadequate at checking this sort of stuff but you might expect the Institution of Civil Engineers to understand the difference...

Yebbut maybe not the low-grade labourers who update their web site.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 05 July, 2020, 02:50:03 pm
For rough estimates there's no point in 3-place conversions between tonne and ton - 2204 v 2240 doesn't really matter for small values in guesstimations.

Now, difference between proper pint and Usanian pint - tantrum!
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 05 July, 2020, 04:18:01 pm
There is a >10% error between long tons (2240 pounds) and short tons (2000 pounds) thobut.
Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 05 July, 2020, 05:42:59 pm
USAnians tend to cut through the dilemma by not using tons at all.  As a general rule the USAnian equivalent of a "44-tonner" weighs 80,000 lbs fully loaded which, given the size of the things, makes me suspect that USAnian road haulage companies get rich by hauling a lot of fresh air around the place.
Title: Re: Arithmetic that makes you cringe
Post by: Moleman76 on 06 July, 2020, 03:24:40 am
many USAnians
suspect that USAnian road haulage companies get rich by hauling
more than the listed weight in their trucks, thereby accelerating the wear and tear on the highways.
Yes, their are weigh stations / scales /  from time to time along the highways, but they are not always staffed, and some truck drivers also take detours around them when they are overweight.
There are often fueling stations on either side of the scales, and some truckers wait until they've been weighed to fill up, if they know that they are close to the limit.

There are also some technological solutions to the weight distribution problem - axles which can be lowered to spread the load out on more contact points.  I would classify these in the "that's fair" category.
Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 06 July, 2020, 01:48:40 pm
Yes, it all gets frightfully confusing with the maths governing axle loading on bridges too, though why rigid dump trucks in Michigan seem to have anything up to eight axles while everyone else seems happy with three is still a mystery to this Unit.  Unless Michigan is in the habit of building bridges out of cheese.

["That's Wisconsin" – Ed.]
Title: Re: Arithmetic that makes you cringe
Post by: nicknack on 06 July, 2020, 02:09:04 pm
Yes, their are weigh stations / scales /  from time to time along the highways, but they are not always staffed, and some truck drivers also take detours around them when they are overweight.


As detailed by Little Feat
Quote
Driven every kind of rig that's ever been made
Driven the back roads so I wouldn't get weighed

Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 06 July, 2020, 02:56:17 pm
Road Research Laboratory (and bearing manufactures for another use): the damage to the highway is proportional to the 4th. power of the loading. A10te axle loaded to 12te will do approx. twice the damage. Puts into perspective the VED on a 2te car and a 60te lorry - and a 0.1te cyclist (inc. bike!).
Very localised damage, e.g. stiletto heels are a different matter, so don't wear them for randonnées!
Title: Re: Arithmetic that makes you cringe
Post by: pcolbeck on 06 July, 2020, 03:42:16 pm
Very localised damage, e.g. stiletto heels are a different matter, so don't wear them for randonnées!

The watch my Grandad bought me for my 18th was a victim of stiletto heels. A 5ft 4inch girl weighing about 7 stone dripping wet can produce a remarkable amount of force in the tiny area at the bottom of a stiletto heeled boot. It was an accident btw the strap clasp failed and and she trod on it as it fell off but still crunch and a very dead watch.
Title: Re: Arithmetic that makes you cringe
Post by: SoreTween on 06 July, 2020, 10:02:02 pm
many USAnians
suspect that USAnian road haulage companies get rich by hauling
more than the listed weight in their trucks, thereby accelerating the wear and tear on the highways.

In early 2018 I was working in Avenza, Italy, above which are mountains.  Mountains with giant bites out of them for they are made marble.  Name a famous Roman statue, it was almost certainly was once a lump of mountain within 10km of Avenza.  There were marble yards everywhere, more common around the industrial estates than charity shops on a UK high street.  Lumps of mountain are precariously perched upon knackered old trucks ^^^up there^^^ and brought down to the sea level yards powered by prayer and very well maintained brakes (accounting for 99.9999% of the maintenance effort expended upon said trucks in the decades since their birth).  One I saw was amazing, it was so bent of frame the offside wheels were skipping & spinning as it accelerated away unloaded.  At the yards techniques that would make a QA man weep/explode/aneurysm all at the same time were employed to remove the lumps of mountain from the trucks. 

You would think after so many hundreds of years of practice they'd have learned to put the baulks of timber across the flatbed so that the unloading telehandler could get it's forks underneath.  No.  Longitudinal timbers are the accepted way and another MUPE/telehandler/rusty tractor/building/rope/whatever preventing the telehandler pushing the lump off the far side was the technique.  Far from every time that worked.  Or, pick it up from the rear and pray.  Fervently.  Many, many times the building I was in shook as another lump got dropped in the yard next door.  They had a pile of bent and broken telehandler forks the size of a transit van.

Anyway...  One Sunday a colleague and I took the tourist tour up to the quarries.  We were shown the small family operations dating back generations and the big commercial outfits responsible for 100's of feet of reduction in one or two peaks.  One point of note in the commentary was the maximum weight of the blocks moved which hasn't changed much since they used oxen, gravity, rope and a plentiful supply of replacement oxen.  28,000 kg? I forget.  Glancing around the yard I asked the guide what happened to the oversize blocks? Each block is clearly marked with it's weight and right in front of us was a 7'x7'x9' or so lump even an amateur could see was waiting for export due to being excellent quality and over weight.  Do they lop a foot off the end or wait until dark to bring it down?  With a smile "I think you understand Italians very well" was the reply.

Happy days.  Cycling in those mountains is something I shall never forget, it wasn't hard to identify and hence avoid the certain death roads.  Simply beautiful part of the world.
Title: Arithmetic that makes you cringe
Post by: Davef on 09 July, 2020, 04:02:42 pm
Coronavirus: Data shows cases in England falling https://www.bbc.co.uk/news/health-53349888

“The Office for National Statistics's estimates one in 3,900 people have Covid-19 - 0.3% of the population.”
Title: Re: Arithmetic that makes you cringe
Post by: mrcharly-YHT on 09 July, 2020, 04:11:27 pm
Failing to understand the difference between m2 and meters square
https://www.ice.org.uk/what-is-civil-engineering/what-do-civil-engineers-do/post-office-tower (https://www.ice.org.uk/what-is-civil-engineering/what-do-civil-engineers-do/post-office-tower)
Quote from: ICE
The project team sank a concrete raft about 8m into the ground to deal with this. The 27m² raft was 1m thick and reinforced with 6 layers of cables.

A square with a side of 10 metres covers 100 square metres, or 100 m2.  An square that 100 metres on a side is 100 metres square and covers a hectare [/sup].

FTFY
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 09 July, 2020, 04:41:49 pm
The Wikipedia article on the hectare gives some illustrations of old units being redefined with new meanings, along the lines of the Norwegian mile mentioned earlier.
Quote
In many countries, metrication redefined or clarified existing measures in terms of metric units. The following legacy units of area have been redefined as being equal to one hectare:[11]

Jerib in Iran
Djerib in Turkey[12]
Gong Qing (公頃/公顷 – gōngqǐng) in Hong Kong / mainland China
Manzana in Argentina
Bunder in The Netherlands (until 1937)[13][14]
Quote
The decare or dekare (/ˈdɛkɑːr, -ɛər/) is derived from deca and are, and is equal to 10 ares or 1000 square metres. It is used in Norway[26] and in the former Ottoman areas of the Middle East and the Balkans (Bulgaria)[27] as a measure of land area. Instead of the name "decare", the names of traditional land measures are usually used, redefined as one decare:

Stremma in Greece[28]
Dunam, dunum, donum, or dönüm in Israel, Palestine, Jordan, Lebanon, Syria and Turkey[29]
Mål is used for decare in Norway, from the old measure of about the same area.
So our "metric or imperial ton" joke/meme/saw is presumably replicated in other parts of the world with the "metric or <traditional> jerib" etc.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 09 July, 2020, 05:16:15 pm
Failing to understand the difference between m2 and meters square
https://www.ice.org.uk/what-is-civil-engineering/what-do-civil-engineers-do/post-office-tower (https://www.ice.org.uk/what-is-civil-engineering/what-do-civil-engineers-do/post-office-tower)
Quote from: ICE
The project team sank a concrete raft about 8m into the ground to deal with this. The 27m² raft was 1m thick and reinforced with 6 layers of cables.

A square with a side of 10 metres covers 100 square metres, or 100 m2.  An square that 100 metres on a side is 100 metres square and covers a hectare [/sup].

FTFY

IFF reader knows what a hectare is.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 09 July, 2020, 05:23:31 pm
IFF reader knows what a hectare is.

I'm not entirely convinced that anyone[1] knows what a hectare is.  It's one of those things you have to look up each time.... :)


[1] Apart from farmers and mistake agents.  And I'm sceptical about the mistake agents.
Title: Re: Arithmetic that makes you cringe
Post by: hatler on 09 July, 2020, 05:25:46 pm
It's easy.  :-)

A hectare is about two and half acres, and an acre is a furlong long by a chain wide, as any fule kno.
Title: Re: Arithmetic that makes you cringe
Post by: Davef on 09 July, 2020, 05:28:49 pm
IFF reader knows what a hectare is.

I'm not entirely convinced that anyone[1] knows what a hectare is.  It's one of those things you have to look up each time.... :)


[1] Apart from farmers and mistake agents.  And I'm sceptical about the mistake agents.
One hectare is a hect of ares
An are is a hect of square metres.
What could be simpler.


Sent from my iPad using Tapatalk
Title: Re: Arithmetic that makes you cringe
Post by: mrcharly-YHT on 09 July, 2020, 05:29:58 pm
It's 1% of a square kilometre.
Title: Re: Arithmetic that makes you cringe
Post by: fuaran on 09 July, 2020, 05:32:44 pm
A hectare is about 1 rugby union pitch, including the bit behind the goals. Or a bit more than a football pitch.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 09 July, 2020, 05:33:08 pm
IFF reader knows what a hectare is.

I'm not entirely convinced that anyone[1] knows what a hectare is.  It's one of those things you have to look up each time.... :)


[1] Apart from farmers and mistake agents.  And I'm sceptical about the mistake agents.
One hectare is a hect of ares
An are is a hect of square metres.
What could be simpler.

It's the hects that are the problem.  See also hectopascals.
Title: Arithmetic that makes you cringe
Post by: Davef on 09 July, 2020, 05:38:02 pm
IFF reader knows what a hectare is.

I'm not entirely convinced that anyone[1] knows what a hectare is.  It's one of those things you have to look up each time.... :)


[1] Apart from farmers and mistake agents.  And I'm sceptical about the mistake agents.
One hectare is a hect of ares
An are is a hect of square metres.
What could be simpler.

It's the hects that are the problem.  See also hectopascals.
I think deci and deca are worse. Get those two the wrong way round would be a hectoblunder.


Sent from my iPad using Tapatalk
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 09 July, 2020, 06:07:05 pm
Better to write deka than deca. Not only is it more distinct from deci, but it preserves the Greek/Latin, hard going up/soft coming down distinction.

And what's the problem with hectopascals?
Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 09 July, 2020, 08:45:11 pm
A hectare is about 1 rugby union pitch, including the bit behind the goals. Or a bit more than a football pitch.
I was going to write that. Before The Event we discussed the fires in NSW at Scouts. Got them to visualise a hectare by comparing it to a rugby pitch, then worked out how many are in a grid square. Then looked at a map of NSW. The largest fire was $scarynumber of hectares. A bit less than the size of Surrey, Sussex and Kent put together.
Title: Re: Arithmetic that makes you cringe
Post by: Pingu on 18 August, 2020, 07:54:08 pm
https://www.theguardian.com/environment/2020/aug/18/atlantic-ocean-plastic-more-than-10-times-previous-estimates

Quote from: Grauniad
That would indicate a concentration in the Atlantic of about 200 million tonnes of these common plastics.

 :facepalm:
Title: Re: Arithmetic that makes you cringe
Post by: Davef on 18 August, 2020, 08:05:58 pm
https://www.theguardian.com/environment/2020/aug/18/atlantic-ocean-plastic-more-than-10-times-previous-estimates

Quote from: Grauniad
That would indicate a concentration in the Atlantic of about 200 million tonnes of these common plastics.

 :facepalm:
That is a lot of plastic. Arithmetic seems in the right ballpark. Not sure concentration is the right word.
Title: Re: Arithmetic that makes you cringe
Post by: LittleWheelsandBig on 18 August, 2020, 09:20:30 pm
A concentration of large amounts of plastic could be something like the Great Garbage Patch, relative to less polluted waters. Trying to be kind here.
Title: Re: Arithmetic that makes you cringe
Post by: Pingu on 19 August, 2020, 12:04:28 am
https://www.theguardian.com/environment/2020/aug/18/atlantic-ocean-plastic-more-than-10-times-previous-estimates

Quote from: Grauniad
That would indicate a concentration in the Atlantic of about 200 million tonnes of these common plastics.

 :facepalm:
That is a lot of plastic. Arithmetic seems in the right ballpark. Not sure concentration is the right word.

Concentration is definitely not the right word  :demon:
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 19 August, 2020, 03:22:13 am
Concentration is the amount of something in a given volume so it's [weight] per [volume]. Both must be specified.
Title: Arithmetic that makes you cringe
Post by: Davef on 19 August, 2020, 06:03:19 am
The estimated concentration is 200MT per Atlantic, an atlantic’ being an obscure non SI unit of volume equal to 310,000,000,000,000,000 cubic metres.  :-)

The zA zeptoAtlantic is a more useful unit for day to day use.
I had 1.7 zA of Guinness yesterday lunchtime.

EDIT: several
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 19 August, 2020, 08:34:08 am
It's only wrong if they've tried to make it maths. Otherwise it's just a lot in one place.
https://g.co/arts/htotPu7pp5KwwdMm6
Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 19 August, 2020, 08:43:19 am
The estimated concentration is 200MT per Atlantic, an atlantic’ being an obscure non SI unit of volume equal to 310,000,000,000,000,000 cubic metres.  :-)

The zA zeptoAtlantic is a more useful unit for day to day use.
I had 1.7 zA of Guinness yesterday lunchtime.

EDIT: several
What's that in Olympic swimming pools?
Title: Re: Arithmetic that makes you cringe
Post by: ElyDave on 19 August, 2020, 09:33:19 am
A hectare is about 1 rugby union pitch, including the bit behind the goals. Or a bit more than a football pitch.

Depends on the size of the in-goal areas, and the width of the pitch, works for something like Twickenham at a full 70m wide and with 22m in-goals, but not a lot of the cabbage patches I used to referee on

Wasn't an acre by definition the area of land that one man with one ox could plough in a day?  I'm not sure which ox was used for the furlong x chain normalisation
Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 19 August, 2020, 11:07:56 am
The estimated concentration is 200MT per Atlantic, an atlantic’ being an obscure non SI unit of volume equal to 310,000,000,000,000,000 cubic metres.  :-)

The zA zeptoAtlantic is a more useful unit for day to day use.
I had 1.7 zA of Guinness yesterday lunchtime.

EDIT: several
What's that in Olympic swimming pools?

Mr Hall is awake earlier than I am.  Damn you, Mr Hall!  Damn you to SWINDON!
Title: Re: Arithmetic that makes you cringe
Post by: PeteB99 on 19 August, 2020, 11:26:49 am
The estimated concentration is 200MT per Atlantic, an atlantic’ being an obscure non SI unit of volume equal to 310,000,000,000,000,000 cubic metres.  :-)

The zA zeptoAtlantic is a more useful unit for day to day use.
I had 1.7 zA of Guinness yesterday lunchtime.

EDIT: several
What's that in Olympic swimming pools?

Mr Hall is awake earlier than I am.  Damn you, Mr Hall!  Damn you to SWINDON!

It's 5123.44 times the area of Wales.

We just need the conversion factor for Wales / Olympic swimming pools to finish the calculation.
Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 19 August, 2020, 11:32:26 am
Lake Superior is about 4 times the size of Wales, if that's any help.

- from “Things I Learned On My Holibobs”, 2016 Edition.
Title: Re: Arithmetic that makes you cringe
Post by: Davef on 19 August, 2020, 11:36:01 am
We have lost a dimension, slipping from volume to area.
Title: Re: Arithmetic that makes you cringe
Post by: citoyen on 19 August, 2020, 11:44:01 am
We just need the conversion factor for Wales / Olympic swimming pools to finish the calculation.

There used to be a website for this but it disappeared some time ago. Also had other useful conversion factors like lengths in double decker buses.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 19 August, 2020, 11:54:00 am
We have lost a dimension, slipping from volume to area.
It got stuck in the Tardis.
Title: Re: Arithmetic that makes you cringe
Post by: cygnet on 19 August, 2020, 11:57:46 am
The Register standards converter still exists, although as a Wales is a unit of area, you would need a Wales x Double-decker bus equivalent to O-SSPs
Title: Re: Arithmetic that makes you cringe
Post by: Wowbagger on 19 August, 2020, 12:57:32 pm
Lake Superior is about 4 times the size of Wales, if that's any help.

- from “Things I Learned On My Holibobs”, 2016 Edition.

Ah, but Lake Superior is mostly flat, whereas Wales mostly isn't.

What's the ratio of Lake Superiors to Carefully Ironed Waleses?
Title: Re: Arithmetic that makes you cringe
Post by: tonyh on 19 August, 2020, 01:02:50 pm
A guess: still 4 (to one significant figure).
Title: Re: Arithmetic that makes you cringe
Post by: citoyen on 19 August, 2020, 02:10:17 pm
The Register standards converter still exists

Just had a look at that. Very similar in functionality to the old website I was thinking of. I wonder if they bought it up...
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 19 August, 2020, 02:27:25 pm
Lake Superior is about 4 times the size of Wales, if that's any help.

- from “Things I Learned On My Holibobs”, 2016 Edition.

Ah, but Lake Superior is mostly flat, whereas Wales mostly isn't.

What's the ratio of Lake Superiors to Carefully Ironed Waleses?

Tell that to the crew of the Edmund Fitzgerald...
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 20 August, 2020, 03:24:39 pm
El Reg's newest unit is the Osman, as a measure for social distance.
Title: Re: Arithmetic that makes you cringe
Post by: fuaran on 11 October, 2020, 01:13:01 pm
A surveyors tape, 30m / 165ft.
https://www.ebay.co.uk/itm/Draper-82753-Fibreglass-Surveyors-Tape-30M-165ft/352346443444
Title: Re: Arithmetic that makes you cringe
Post by: hatler on 11 October, 2020, 01:19:25 pm
Draper !   One tip from my dad, "Never buy Draper tools."
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 11 October, 2020, 02:26:11 pm
A surveyors tape, 30m / 165ft.
https://www.ebay.co.uk/itm/Draper-82753-Fibreglass-Surveyors-Tape-30M-165ft/352346443444

I think that's a genuine mistype/error, as a 50m/165ft tape appears in the mini ads above the main one.
Title: Re: Arithmetic that makes you cringe
Post by: orienteer on 11 October, 2020, 03:59:18 pm
You can measure 165ft on a 50m tape  :demon:
Title: Re: Arithmetic that makes you cringe
Post by: Diver300 on 11 October, 2020, 05:49:48 pm
You can measure 165ft on a 50m tape  :demon:
Well a tape in two units will presumably finish each unit at a round number. 50 m is very close to 164 ft, so they've stopped the markings at 50 m on one side and 55 yards / 165 ft on the other.

I would be most amused to see a tape stop at 164 ft and 129/256 of an inch, just to annoy anyone using imperial units.
Title: Re: Arithmetic that makes you cringe
Post by: Pickled Onion on 16 October, 2020, 08:35:02 am
News on the Today programme: "Wetherspoons profits have fallen by 130%" in the headlines, then repeated by the financial correspondent.

Wow. Just Wow.
Title: Re: Arithmetic that makes you cringe
Post by: Asterix, the former Gaul. on 16 October, 2020, 09:21:30 am
News on the Today programme: "Wetherspoons profits have fallen by 130%" in the headlines, then repeated by the financial correspondent.

Wow. Just Wow.

I have to say that cringing was not my reaction to that news.
Title: Re: Arithmetic that makes you cringe
Post by: hatler on 16 October, 2020, 09:42:29 am
News on the Today programme: "Wetherspoons profits have fallen by 130%" in the headlines, then repeated by the financial correspondent.

Wow. Just Wow.
Is that not just a smartarse way of saying they've had a loss that was 30% of the last period's profits.
Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 16 October, 2020, 09:51:38 am
News on the Today programme: "Wetherspoons profits have fallen by 130%" in the headlines, then repeated by the financial correspondent.

Wow. Just Wow.

We need an “Arithmetic that makes me feel like dancing” thread :demon:
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 15 November, 2020, 03:42:20 pm
Not sure whether this belongs here or in The Last Trump:

"Do these scatter plots reveal fraudulent vote-switching in Michigan?"

https://youtu.be/aokNwKx7gM8
Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 17 November, 2020, 08:53:11 am
Not sure whether this belongs here or in The Last Trump:

"Do these scatter plots reveal fraudulent vote-switching in Michigan?"

https://youtu.be/aokNwKx7gM8

Nice. Top book and Rubik's cube placement too.
Title: Re: Arithmetic that makes you cringe
Post by: Davef on 17 November, 2020, 08:54:26 am
Not sure whether this belongs here or in The Last Trump:

"Do these scatter plots reveal fraudulent vote-switching in Michigan?"

https://youtu.be/aokNwKx7gM8

Nice. Top book and Rubik's cube placement too.
It works - just ordered a copy
Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 17 November, 2020, 09:07:44 am
Not sure whether this belongs here or in The Last Trump:

"Do these scatter plots reveal fraudulent vote-switching in Michigan?"

https://youtu.be/aokNwKx7gM8

Nice. Top book and Rubik's cube placement too.
It works - just ordered a copy
Heh. I've seen him on stage a couple of times as part of the Festival of the Spoken Nerd. Top spreadsheet fun and measuring Pi using a pie. Next challenge was to meausre the Planck constant using a plank.
Title: Re: Arithmetic that makes you cringe
Post by: Pingu on 04 December, 2020, 12:25:44 am
A new unit for me: https://www.theguardian.com/business/2020/dec/04/bank-of-england-criticised-for-losing-track-of-50bn-of-banknotes

Quote from: Grauniad
equivalent to a stack of £5 notes more than 800 miles high
Title: Re: Arithmetic that makes you cringe
Post by: Davef on 04 December, 2020, 08:30:14 am
Not sure whether this belongs here or in The Last Trump:

"Do these scatter plots reveal fraudulent vote-switching in Michigan?"

https://youtu.be/aokNwKx7gM8

Nice. Top book and Rubik's cube placement too.
It works - just ordered a copy
Heh. I've seen him on stage a couple of times as part of the Festival of the Spoken Nerd. Top spreadsheet fun and measuring Pi using a pie. Next challenge was to meausre the Planck constant using a plank.
I have calculated pi using planks.

(dropping toothpicks onto a planked floor and counting the number that cross joints).
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 09 December, 2020, 08:10:22 pm
Quote
a hill with a steepness of 1 in 5 or greater (that's anything between eight and 13 per cent).
It didn't really detract from the reading though.
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 17 December, 2020, 08:56:43 pm
Our very own IanDG posted this on Facebook.

(https://scontent.flhr2-2.fna.fbcdn.net/v/t1.0-9/131904787_10158821903897486_7972848373121433181_o.jpg?_nc_cat=104&ccb=2&_nc_sid=730e14&_nc_ohc=wYT6pOyfZFIAX-EAVNH&_nc_ht=scontent.flhr2-2.fna&oh=4d033b0aa60fc06cea236b64231c011c&oe=60013B56)
Title: Re: Arithmetic that makes you cringe
Post by: citoyen on 26 January, 2021, 03:52:11 pm
What am I missing here?

"Within digital recruitment channels, Facebook paid advertising is the most effective, generating 68% of new recruits, while 51% comes from SEO efforts, and 46% from remarketing."
https://memberpress.com/blog/useful-membership-site-statistics-you-should-know/
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 26 January, 2021, 10:05:24 pm
Supposedly this is a trike:
(https://i2-prod.bristolpost.co.uk/incoming/article4929997.ece/ALTERNATES/s615b/0_zedify.jpg)
https://www.bristolpost.co.uk/news/bristol-news/fleet-electric-cargo-delivery-bikes-4930065
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 27 January, 2021, 08:33:09 am
No, it's a 4-wheeled bike, obviously. Quike it is.
Title: Re: Arithmetic that makes you cringe
Post by: Polar Bear on 27 January, 2021, 08:54:20 am
Surely it's a quadricycle, no?
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 27 January, 2021, 11:08:04 am
It is a quad.
Title: Re: Arithmetic that makes you cringe
Post by: Davef on 27 January, 2021, 11:39:39 am
It is 3 bicycles- 2 of them in close formation.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 28 January, 2021, 09:54:32 am
Bike, trike, quike.
Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 28 January, 2021, 11:30:08 am
Bike, trike, quike.

… Quinquireme of Nineveh from distant Ophir?
Title: Re: Arithmetic that makes you cringe
Post by: Wowbagger on 28 January, 2021, 11:32:40 am
Bike, trike, quike.

… Quinquireme of Nineveh from distant Ophir?

But can it go where a car goes?
Title: Re: Arithmetic that makes you cringe
Post by: hatler on 28 January, 2021, 11:34:50 am
Rowing home to haven in sunny Palestine,
Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 28 January, 2021, 11:50:19 am
With a cargo of ivory,
And AK47s and peacocks,
Sandalwood, cedarwood*, and sweet white wine

* wouldn’t it have been easier to hew the cedars out of Lebanon?
Title: Re: Arithmetic that makes you cringe
Post by: chris on 06 February, 2021, 08:14:09 am
From digitalcameraworld.com, proof that PI is equal to 1 -

“To put it into more dramatic context, if you laid all of those 150 million lenses end to end, they would measure approximately 7,736 miles – which is nearly enough to wrap around planet Earth, whose diameter is around 7,917 miles.”
Title: Re: Arithmetic that makes you cringe
Post by: Davef on 06 February, 2021, 12:21:11 pm
..... starting in Alaska and heading due west.
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 26 February, 2021, 12:47:47 am
Beeb story about breast reduction:

Quote
Lyndsey Nurse said she understood all too well Mrs Michaud's struggle. With 36 K breasts, her chest weighs 2st (13kg), the equivalent of 14 bags of sugar.

What size are those sugar bags?

To be fair, 2 stone is 14 2lb bags of sugar but my sugar bags have been a kilo for AGES now.
2 stone is less than 13kg thobut.
Title: Arithmetic that makes you cringe
Post by: citoyen on 26 February, 2021, 08:09:03 am
Beeb story about breast reduction:

Quote
Lyndsey Nurse said she understood all too well Mrs Michaud's struggle. With 36 K breasts, her chest weighs 2st (13kg), the equivalent of 14 bags of sugar.

What size are those sugar bags?

To be fair, 2 stone is 14 2lb bags of sugar but my sugar bags have been a kilo for AGES now.
2 stone is less than 13kg thobut.

This is infuriating!

I’m all in favour of rounding off conversions when the numbers are approximate (presumably her breasts don’t weigh *exactly* 2st, so 13kg is probably just as accurate) but a bit of intelligence needs to be applied to ensure the numbers still make sense.
Title: Re: Arithmetic that makes you cringe
Post by: Davef on 26 February, 2021, 09:04:11 am
Beeb story about breast reduction:

Quote
Lyndsey Nurse said she understood all too well Mrs Michaud's struggle. With 36 K breasts, her chest weighs 2st (13kg), the equivalent of 14 bags of sugar.

What size are those sugar bags?

To be fair, 2 stone is 14 2lb bags of sugar but my sugar bags have been a kilo for AGES now.
2 stone is less than 13kg thobut.
It is rounded to an integer number of sugar bags per breast obviously. Asymmetry at that order of magnitude could be problematic.
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 26 February, 2021, 02:01:04 pm
I am on injected medication I take three times per week.
My supplier phoned yesterday evening.

'How many syringes do you have left?'
'Eleven'
'When are you next due to inject?'
'Tonight.'
'So you'll have thirteen left?'
'No, I'll have ten.'

!!!
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 27 February, 2021, 08:17:47 am
Well, eleven does sound similar to fourteen, innit.
Title: Re: Arithmetic that makes you cringe
Post by: Pickled Onion on 27 April, 2021, 08:23:29 pm
A puff piece from my local council:
Quote
Healthy
Beat the Street - active project that got 8,000 residents walking, running and cycling 73,000 miles from March to May 2019

Ignoring the fact they're bragging about this nearly two years later, that works out at roughly 160 metres per person per day. Probably achievable with a few trips from the sofa to the fridge.
Title: Re: Arithmetic that makes you cringe
Post by: JStone on 11 May, 2021, 11:38:21 am
According to Tesco, 5 x 10 = 51. Still, every little helps - their profits

(https://live.staticflickr.com/65535/51171904106_8f081fecce_z.jpg) (https://flic.kr/p/2kXTohJ)

Title: Re: Arithmetic that makes you cringe
Post by: grams on 11 May, 2021, 12:32:03 pm
If an onion weighs 120g on average then the maths works out.

It should say £0.102 each though perhaps that would scare the horses.

(It belongs in UI design that makes you cringe)
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 11 May, 2021, 04:52:28 pm
On a proggy about rivers, boat could cruise at 9 knots/hour. Ignoring cruise, assuming fuel for 24h, how fast would it be going after 24h?

Some article I saw, can't unforget what, one nautical mile with metric in brackets: 1,9** (can't remember the last 2 figures). About 1,850m? Even 1,760 doesn't come to that - I did wonder if the author had used yards in a mile.
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 11 May, 2021, 06:32:51 pm
The pedant in me dislikes knots per hour.

Either knots or nautical miles per hour.

Perleaze!
Title: Re: Arithmetic that makes you cringe
Post by: SteveC on 11 May, 2021, 06:38:16 pm
Some article I saw, can't unforget what, one nautical mile with metric in brackets: 1,9** (can't remember the last 2 figures). About 1,850m? Even 1,760 doesn't come to that - I did wonder if the author had used yards in a mile.
According to the usual source of (mis)information, the nautical mile is now defined as 1852m.
Title: Re: Arithmetic that makes you cringe
Post by: Davef on 11 May, 2021, 07:37:39 pm
The pedant in me dislikes knots per hour.

Either knots or nautical miles per hour.

Perleaze!
Perhaps they were referring to an acceleration of 9 knots/hour, to give a final velocity of 216 knots.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 12 May, 2021, 10:36:35 am
If an onion weighs 120g on average then the maths works out.

It should say £0.102 each though perhaps that would scare the horses.

(It belongs in UI design that makes you cringe)

This sort of thing happens all the time where fractional pennies exist, but aren't rendered.  Sort of thing they do to keep accounts auditors on their toes.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 06 June, 2021, 04:58:11 pm
Item on the Beeb's site:
"Two-time defending champion Mo Farah's hopes of representing Great Britain in the Olympic 10,000m seem to be over after he fell short of the qualifying mark in the European 10,000m Cup.

The 38-year-old was eighth, behind fellow Briton Marc Scott, in a race that doubled as the Olympic trial.

Farah's time of 27 minutes 50.54 seconds in Birmingham was more than 22 seconds short of the required time."
Title: Re: Arithmetic that makes you cringe
Post by: fd3 on 06 June, 2021, 11:33:29 pm
The pedant in me dislikes knots per hour.
Thanks for that, I know f-all about boats but my first through on reading that was "isn't knots a unit of speed?"  (I believe due to the expression "travelling at a rate of knots" which implies that whatever a knot is, it measure speed).
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 07 June, 2021, 01:02:43 am
A knot is a nautical mile per hour.

A nautical mile (1852 metres) is a bit more than a statute mile (1609 metres).
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 07 June, 2021, 08:11:59 am
The pedant in me dislikes knots per hour.
Thanks for that, I know f-all about boats but my first through on reading that was "isn't knots a unit of speed?"  (I believe due to the expression "travelling at a rate of knots" which implies that whatever a knot is, it measure speed).
A rate of knots would be acceleration.
Title: Re: Arithmetic that makes you cringe
Post by: ravenbait on 07 June, 2021, 12:29:29 pm

A rate of knots would be acceleration.

Does the phrase not date back to the time when speed was determined by counting knots in a rope attached to a drag that was put out the stern of a ship? So that would be "rate of knots counted per 30 seconds."

Sam
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 07 June, 2021, 01:54:25 pm

A rate of knots would be acceleration.

Does the phrase not date back to the time when speed was determined by counting knots in a rope attached to a drag that was put out the stern of a ship? So that would be "rate of knots counted per 30 seconds."

Sam

Probably for something like "per one turn of the small glass". It's probably OK to use if if you're still timing things other than eggs with sand-glasses, but most of us have moved on.

"Knots per hour" is just bloody ignorant (and/or BBC standard).
Title: Re: Arithmetic that makes you cringe
Post by: hatler on 07 June, 2021, 02:08:23 pm

A rate of knots would be acceleration.

Does the phrase not date back to the time when speed was determined by counting knots in a rope attached to a drag that was put out the stern of a ship? So that would be "rate of knots counted per 30 seconds."

Sam
I've done that.  With one of these (https://collections.rmg.co.uk/collections/objects/42932.html). Bizarrely, for reasons I can't remember, the sand glass counts to 14 seconds. If I could be bothered I'd sit down and work it out. It probably means the knots in the line are x fathoms apart.
Title: Re: Arithmetic that makes you cringe
Post by: ravenbait on 07 June, 2021, 02:13:45 pm

Probably for something like "per one turn of the small glass". It's probably OK to use if if you're still timing things other than eggs with sand-glasses, but most of us have moved on.

Lots of idioms remain in use after people no longer do the thing that coined the phrase.  We no longer use guns in naval warfare that have an accurate range best described as "near enough to piss on", but we still use the phrase "a long shot" to refer to something being a slim chance. And at least some of us know that the phrase is "toe the line" (not "tow the line"), and nobody is expected to line up barefoot on deck any more.

Quote
"Knots per hour" is just bloody ignorant (and/or BBC standard).

Completely agree.

Sam
Title: Re: Arithmetic that makes you cringe
Post by: PeteB99 on 07 June, 2021, 02:18:08 pm

A rate of knots would be acceleration.

Does the phrase not date back to the time when speed was determined by counting knots in a rope attached to a drag that was put out the stern of a ship? So that would be "rate of knots counted per 30 seconds."

Sam
I've done that.  With one of these (https://collections.rmg.co.uk/collections/objects/42932.html). Bizarrely, for reasons I can't remember, the sand glass counts to 14 seconds. If I could be bothered I'd sit down and work it out. It probably means the knots in the line are x fathoms apart.

Correct. Although the usual glass used was a 28 seconds one with the knots 7 fathoms apart.

That's assuming my memory is still functioning
Title: Re: Arithmetic that makes you cringe
Post by: hatler on 07 June, 2021, 02:19:10 pm
Ooo. Possibly it was 28 seconds. It's a while since I last did this.
Title: Re: Arithmetic that makes you cringe
Post by: PeteB99 on 07 June, 2021, 02:28:05 pm
I only ever did it once as an exercise in making a chip log in the sea scouts. I'm pretty sure the antique timer glass they gave us to work with was 28 secs.We had to build the rest with assorted bits of wood a long line and a measured fathom stick. It worked quite well when we tested it.
Title: Re: Arithmetic that makes you cringe
Post by: Pingu on 19 July, 2021, 10:12:14 am
Quote
more than 53,969

So maybe 53,970?
Title: Re: Arithmetic that makes you cringe
Post by: Pingu on 27 July, 2021, 08:40:33 pm
Quote
Each system will consist of approximately two 25-centimeter (10in) telescopes with a camera

https://www.theguardian.com/science/2021/jul/27/galileo-project-search-signs-extraterrestrial-technology
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 05 August, 2021, 09:23:57 am
This could also be under crazy foreigners: in Utah some contenders for a Darwin Award are hanging hammocks from HV lines; the sheriff warn "...that power lines carry 75,000 kilovolts of power and that the energy can jump between lines,...".
75MV!!! as power?
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 05 August, 2021, 09:55:06 am
Power has been used colloquially to mean electricity for years, probably for over a century.
Title: Re: Arithmetic that makes you cringe
Post by: Feanor on 05 August, 2021, 10:04:08 am
I'm OK with that too.
I parse it as the lines are carrying power, at a voltage of 75 kV.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 06 August, 2021, 12:10:04 am
It's the "volts of power" that throws me more than the use of 'power' to mean 'electricity'.  "Carrying power at 75kV" would be fine, but I'm generally of the opinion that once you mention Volts, Amperes or Watts, you really ought to use them correctly.

But since this is the cringeworthy aritmetic thread, not the grammar one, the real error is that they say "75,000 kilovolts", when they mean 75 kilovolts / 75,000 volts.  If it were 75MV it would seriously hamper the hammock-hanging efforts, on account of having reduced everything in the vicinity to plasma.  Simple typo that would easily sneak past a proofreader with limited knowledge of electricity.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 06 August, 2021, 09:46:04 am
It could have slipped past a proofreader but more likely it never met one. Anyway, I'd parse the whole thing as "We need to stop stupid people doing dangerous things. The technical details don't matter (if they understood them, they wouldn't be doing these things in the first place), we just need to emphasize the danger."
Title: Re: Arithmetic that makes you cringe
Post by: Diver300 on 08 August, 2021, 01:01:55 pm
(https://mtrak.co.uk/pictures/personal/Cl_maths_wrong.png)

:facepalm:

If anyone hasn't worked out the problem here, the concentration for 1000 litres is probably correct, but should go up for smaller quantities of water and down for larger quantities.
Title: Re: Arithmetic that makes you cringe
Post by: chrisbainbridge on 14 August, 2021, 10:10:06 pm
BBC reporter stating that temperature of 48degC in Sicily is half way to boiling point.
No, just no!
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 14 August, 2021, 10:21:19 pm
Of 5-methoxy-2-tetralone, presumably...   :facepalm:
Title: Re: Arithmetic that makes you cringe
Post by: Basil on 14 August, 2021, 10:24:35 pm
BBC reporter stating that temperature of 48degC in Sicily is half way to boiling point.
No, just no!

Ah Chris beat me to it.
I guess half way to boiling point would be roughly  -186.575c.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 16 August, 2021, 08:09:17 am
Ordnance Survey's Tour 3 map of Lake District:
1:110 000 scale             1 cm to 1 km - 1 inch to 1¾ miles.
Explains 'friendly fire'.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 16 August, 2021, 10:00:29 am
BBC reporter stating that temperature of 48degC in Sicily is half way to boiling point.
No, just no!
Alternatively, it's the triumph or arithmetic over physics.
Title: Re: Arithmetic that makes you cringe
Post by: Lightning Phil on 16 August, 2021, 10:11:33 am
BBC reporter stating that temperature of 48degC in Sicily is half way to boiling point.
No, just no!
Alternatively, it's the triumph or arithmetic over physics.

Halfway between freezing and boiling point of water will be what they meant.
Title: Re: Arithmetic that makes you cringe
Post by: ravenbait on 16 August, 2021, 11:08:59 am
Ordnance Survey's Tour 3 map of Lake District:
1:110 000 scale             1 cm to 1 km - 1 inch to 1¾ miles.
Explains 'friendly fire'.

Makes me think of the house in House of Leaves.

Sam
Title: Re: Arithmetic that makes you cringe
Post by: ian on 16 August, 2021, 11:12:16 am
BBC reporter stating that temperature of 48degC in Sicily is half way to boiling point.
No, just no!
Alternatively, it's the triumph or arithmetic over physics.

Halfway between freezing and boiling point of water will be what they meant.

That's how I read it (and I'm sure most other readers).
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 17 August, 2021, 08:54:47 am
Something very like that but possibly simpler. Would a Usanian say it at 122F or 106? I'm thinking the latter.
Title: Re: Arithmetic that makes you cringe
Post by: Guy on 07 October, 2021, 10:48:32 am
I have just completed the IT Local Security Officer course, scoring 38 out of a possible 38 in the final test.

My stickyfoot says:
Quote
Course Grade: 98.68%

 ???
Title: Re: Arithmetic that makes you cringe
Post by: philip on 07 October, 2021, 10:55:58 am
I have just completed the IT Local Security Officer course, scoring 38 out of a possible 38 in the final test.

My stickyfoot says:
Quote
Course Grade: 98.68%

 ???
Looks like you really scored 37.5, which can be rounded to 38 but also left unrounded as 98.68%.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 07 October, 2021, 11:53:44 am
You're supposed to hack in and fix the results yourself.
Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 03 November, 2021, 07:19:54 pm
I'm just looking at a drawing of a sheet piling layout. It has dimensions on it, for example 6670.052.  The units are millimetres.  This means what ever it is is being measured to the nearest 0.001 mm . That's 1 micron. Human hair is 70 microns. Joe average bacteria are 1-2 microns diameter.  Sheet piles (GBFO lumps of steel) are not manufactured to such tolerances.
Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 03 November, 2021, 07:31:25 pm
Is it (badly) converted from some other set of units by an idiot?
Title: Re: Arithmetic that makes you cringe
Post by: rafletcher on 03 November, 2021, 07:58:00 pm
Nah, it’s a CAD drawing and you can be super accurate….  even if the building won’t be closer than half a brick.
Title: Re: Arithmetic that makes you cringe
Post by: Ashaman42 on 03 November, 2021, 08:04:06 pm
Oh yeah, I've had students giving me diagrams of parts to be manufactured where clearance hole positions are specified to 0.001mm.
Title: Re: Arithmetic that makes you cringe
Post by: Ashaman42 on 03 November, 2021, 08:04:40 pm
And lecturers for that matter.
Title: Re: Arithmetic that makes you cringe
Post by: hatler on 03 November, 2021, 08:12:47 pm
I remember given a helmsman on an RFA tug a heading to half a degree. He laughed. I didn't do that again.
Title: Re: Arithmetic that makes you cringe
Post by: cygnet on 03 November, 2021, 08:37:08 pm
Nah, it’s a CAD drawing and you can be super accurate….  even if the building won’t be closer than half a brick.

CAD in the wrong hands gives a laughable impression of what is buildable, leading to unrealistic expectations.
Title: Re: Arithmetic that makes you cringe
Post by: Ashaman42 on 03 November, 2021, 08:45:06 pm
That is the other joy I get. Designs that would require spanners/allen keys to phase through solid matter to do fixings up.
Title: Re: Arithmetic that makes you cringe
Post by: hatler on 04 November, 2021, 12:03:44 pm
Oooof. On two levels.

Quote
"We have 8,5000 people dying each year of fuel poverty - that's a hundred people a day," he said.

From here (https://www.bbc.co.uk/news/uk-england-london-59163068).
Title: Re: Arithmetic that makes you cringe
Post by: Pickled Onion on 04 November, 2021, 07:46:39 pm
You missed the "during winter" off the end of the quote. So if that zero is the obvious typo, assuming people only die of fuel poverty from December to February, it sort of adds up correctly.
Title: Re: Arithmetic that makes you cringe
Post by: Pickled Onion on 04 November, 2021, 07:56:54 pm
I have just completed the IT Local Security Officer course, scoring 38 out of a possible 38 in the final test.

My stickyfoot says:
Quote
Course Grade: 98.68%

 ???

Work asked us to "help out" some numeracy charity by completing their test.

"Congratulations, you scored 100%. Click here, here and here to see how you could improve your score"
Title: Re: Arithmetic that makes you cringe
Post by: hatler on 04 November, 2021, 08:24:59 pm
You missed the "during winter" off the end of the quote. So if that zero is the obvious typo, assuming people only die of fuel poverty from December to February, it sort of adds up correctly.
Fair point. Mis-quoting is something I despise. And if that figure is 8,500 and not 85,000 then it all stacks up.
Title: Re: Arithmetic that makes you cringe
Post by: fimm on 05 November, 2021, 03:45:44 pm
https://twitter.com/GiveMeSpace3/status/1456622706615586819
Quote
Study finds that one in 53 people in the UK has symptomatic virus - down from one in 56 a week before.
Title: Re: Arithmetic that makes you cringe
Post by: Moleman76 on 05 November, 2021, 11:39:21 pm
Nah, it’s a CAD drawing and you can be super accurate….  even if the building won’t be closer than half a brick.

CAD in the wrong hands gives a laughable impression of what is buildable, leading to unrealistic expectations.

From time to time I help out with "constructability reviews" of publicly funded projects (schools, mostly).  The usual focus is "before you release these documents for bidders, can a group of architects and engineers help the design team identify things that won't fit, where drawings show different things, etc., so they can be corrected?"  However, when I see dimensions in x/256", I usually comment that they need to reset the precision or face guffaws from the builders.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 06 November, 2021, 08:46:47 am
https://twitter.com/GiveMeSpace3/status/1456622706615586819
Quote
Study finds that one in 53 people in the UK has symptomatic virus - down from one in 56 a week before.
I do wish that all these figures were given as percentages - so much simpler.
Then there's the rounding: no, 9,790 is not nearly 10,000. To be generous, I'll give you almost 9,800.

BTW, a scientific site mentioned atmospheric CO2 as 4% - it's actually about 415ppm.
Title: Re: Arithmetic that makes you cringe
Post by: ian on 09 November, 2021, 09:24:06 am
I think we'd all be dead if the atmosphere was 4% carbon dioxide (but we shouldn't give industry a target). I presume they meant 0.04%.

I do prefer 1-in-50 people approach rather than relative numbers like percentages. It's a big annoyance in medical papers and reporting when they write that such-and-such is 20% better, tell me how many people the drug will fix. It's become a sleight of hand to fudge minimal effects.
Title: Re: Arithmetic that makes you cringe
Post by: chrisbainbridge on 09 November, 2021, 03:38:03 pm
I think we'd all be dead if the atmosphere was 4% carbon dioxide (but we shouldn't give industry a target). I presume they meant 0.04%.

I do prefer 1-in-50 people approach rather than relative numbers like percentages. It's a big annoyance in medical papers and reporting when they write that such-and-such is 20% better, tell me how many people the drug will fix. It's become a sleight of hand to fudge minimal effects.
Exactly
Title: Re: Arithmetic that makes you cringe
Post by: hatler on 12 November, 2021, 04:52:48 pm
Woops.

https://www.bbc.co.uk/news/business-59119103

Quote
An electric scooter that can go 100 kmph (62 mph)? Meet the sleek new machine that's designed to leave the clunky scooters you see buzzing around suburban High Streets, in the dust.

Looks like the sub didn't get to this one in time.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 13 November, 2021, 09:08:30 am
That'll beat Elon to Mars!
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 13 November, 2021, 12:58:33 pm
The abbreviations are a bit clunky perhaps but I don't see anything wrong with the arithmetic. Not that that guarantees there's nothing wrong.
Title: Re: Arithmetic that makes you cringe
Post by: hatler on 13 November, 2021, 01:01:29 pm
kmph isn't a unit.
The "?" after the "(62mph)?" indicates the poor journo doesn't know/couldn't work out what 100kph is in mph and would have put that there as an appeal to the sub-editor to check and correct if necessary.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 13 November, 2021, 01:06:23 pm
kmph shouldn't be a unit but is commonly used and the "?" applies to the whole sentence, as in "[Can you believe/Would you want/etc] An electric scooter that can go 100 kmph (62 mph)?" I'd call it dodgy writing rather than arithmetic.
Title: Re: Arithmetic that makes you cringe
Post by: Pickled Onion on 13 November, 2021, 07:53:14 pm
Trying to compare fridge freezers on the JL site. Apparently the NEFF one has a capacity of 630.0 litres. But still fits in a space H177.2 x W55.8 x D54.5cm. I wonder if it says "FREE FOR USE OF PUBLIC" on it as well.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 14 November, 2021, 08:15:19 am
I see it as kilo-miles-per-hour. 100,000 mph would break the speed limit on most roads.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 14 November, 2021, 08:18:23 am
It has negative insulation, so it's bigger on the inside... - oh, I've had an idea for an SF series.
Title: Re: Arithmetic that makes you cringe
Post by: Pickled Onion on 14 November, 2021, 08:27:15 pm
Negative insulation doesn't sound like a great feature for a fridge  ;)
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 14 November, 2021, 08:50:00 pm
Depends who's hiding in it.  ;)
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 14 November, 2021, 09:41:46 pm
This story seems unable to count to six reliably.
https://www.mirror.co.uk/news/uk-news/young-parents-welcome-200-million-25414422?utm_source=facebook.com&utm_medium=social&utm_campaign=mirror_main&fbclid=IwAR0SWrGEhP5426htjZOxdltLx8td7-mAYHCkXegMvZoVQQhsBO4r0Shz5DA (https://www.mirror.co.uk/news/uk-news/young-parents-welcome-200-million-25414422?utm_source=facebook.com&utm_medium=social&utm_campaign=mirror_main&fbclid=IwAR0SWrGEhP5426htjZOxdltLx8td7-mAYHCkXegMvZoVQQhsBO4r0Shz5DA)

Quote
Couple welcome '200m to one' identical triplets and now have 4 kids under two
Ellie Dudfield, 21, and Billy Revell, 20, are adjusting to life as a family of five after welcoming a set of identical triplets - the three boys were born 12 weeks early and had a 40% chance of survival

Young couple have toddler, followed by triplets and are referred to as 'a family of five'…

I think 2 + 1 + 3 = 6...
Title: Re: Arithmetic that makes you cringe
Post by: Pingu on 20 November, 2021, 11:08:26 pm
I had to do that on my fingers   ::-)
Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 20 November, 2021, 11:51:42 pm
You can’t spell “millennia” either, Grandad, so bugger off.
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 21 November, 2021, 01:24:26 am
I had to do that on my fingers   ::-)

Even if you had to do it on your fingers, methinks you would have been able to count to ten at some stage before your eighth birthday.

What really gets me is how these things are propagated unchecked & uncorrected on social meeja.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 21 November, 2021, 10:43:09 am
Oh shit, I've lived in 9. Decades, not centuries.
Title: Re: Arithmetic that makes you cringe
Post by: Basil on 21 November, 2021, 02:26:36 pm
Oh shit, I've lived in 9. Decades, not centuries.

Me too.
Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 08 December, 2021, 06:22:59 pm
Sign on the back of a minibus today:

Please leave 8 feet (3m) for wheelchair ramp.

You sure about that?
Title: Re: Arithmetic that makes you cringe
Post by: Feanor on 08 December, 2021, 06:57:24 pm
Sign on the back of a minibus today:

Please leave 8 feet (3m) for wheelchair ramp.

You sure about that?

I think that's OK.
On signage, you don't need or want decimal places; no-one will be using a tape measure.
You just want an integer number of meet or feeters.

So if we say 8 ft, that is 2.4384m.
To round this to integer values, you might choose 2m, but since it's wheelchair access and the value of 8ft might be regarded as a minimum, you might not want to round down.
So rounding up to 3m seems reasonable to me.


Title: Re: Arithmetic that makes you cringe
Post by: phantasmagoriana on 08 December, 2021, 07:04:28 pm
Sign on the back of a minibus today:

Please leave 8 feet (3m) for wheelchair ramp.

You sure about that?

I think that's OK.
On signage, you don't need or want decimal places; no-one will be using a tape measure.
You just want an integer number of meet or feeters.

So if we say 8 ft, that is 2.4384m.
To round this to integer values, you might choose 2m, but since it's wheelchair access and the value of 8ft might be regarded as a minimum, you might not want to round down.
So rounding up to 3m seems reasonable to me.

But why not just say 10ft? ???
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 08 December, 2021, 07:19:39 pm
Sign on the back of a minibus today:
Please leave 8 feet (3m) for wheelchair ramp.
You sure about that?
I think that's OK.
On signage, you don't need or want decimal places; no-one will be using a tape measure.
You just want an integer number of meet or feeters.
So if we say 8 ft, that is 2.4384m.
To round this to integer values, you might choose 2m, but since it's wheelchair access and the value of 8ft might be regarded as a minimum, you might not want to round down.
So rounding up to 3m seems reasonable to me.

3 metres is 10 feet in fairly accurate round numbers.
Title: Re: Arithmetic that makes you cringe
Post by: Feanor on 08 December, 2021, 07:31:16 pm
Sign on the back of a minibus today:

Please leave 8 feet (3m) for wheelchair ramp.

You sure about that?

I think that's OK.
On signage, you don't need or want decimal places; no-one will be using a tape measure.
You just want an integer number of meet or feeters.

So if we say 8 ft, that is 2.4384m.
To round this to integer values, you might choose 2m, but since it's wheelchair access and the value of 8ft might be regarded as a minimum, you might not want to round down.
So rounding up to 3m seems reasonable to me.

But why not just say 10ft? ???

Because the original value may have been specified in ft.

Yes, you could convert to integer m, then back-calculate a revised ft value.
But that does not really add any value to the procedure.

Leaving 8ft or 3m both satisfy the requirement.
No need to complicate it.
Title: Re: Arithmetic that makes you cringe
Post by: grams on 08 December, 2021, 11:50:25 pm
Both numbers are likely padded upwards well above the actual minimum to account for misers and chancers.
Title: Re: Arithmetic that makes you cringe
Post by: barakta on 11 December, 2021, 05:17:53 pm
A wheelchair using friend of mine has a heavily adapted van. Because people will NOT leave the 2m+ she needs to get in and out, she has an inflatable cone on a string which she leaves out behind her parked van to try and deter people from blocking the necessary space.

It's not 100% effective, but it works more often than not. It also proves anyone blocking her has actively chosen to do so as they have to go and move the cone...
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 11 December, 2021, 05:24:09 pm
I recently found myself in traffic behind a converted van with no less than six (6) variations on the "please leave room for wheelchair access" sign affixed.  Two of which specified (conflicting) distances.  Not that it matters, even if people read them, common sense, politeness and basic human decency all go out the window as soon as car parking becomes involved.
Title: Re: Arithmetic that makes you cringe
Post by: grams on 21 December, 2021, 05:21:57 pm
The not-at-all macabrely named HumanForest bike sharing app at the end of a ride:
(http://www.fondantfancies.com/images/humanforest.jpg)

There's no context I'm omitting here - this is the first and only time it's displayed how much this ride and/or parking(?!) might cost.

Also the red christmas decorations on the tree initially made me think this location was crossed out. Thanks zany art department.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 21 December, 2021, 05:33:08 pm
The not-at-all macabrely named HumanForest bike sharing app at the end of a ride:
(http://www.fondantfancies.com/images/humanforest.jpg)

"If you see a negative fee, you're parking for free!" presumably means "Sorry, we're just bad at computers."

(Using a negative number to represent free parking in some database isn't inherently a bad idea, but leaking that representation out to the user is just sloppy.)
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 21 December, 2021, 05:38:20 pm
I'd have said they just wanted an excuse to use a not particularly good rhyme. Also, your  image isn't showing for me at all in the post (but I saw it by pasting it into my browser).
Title: Re: Arithmetic that makes you cringe
Post by: grams on 21 December, 2021, 05:46:11 pm
My total guess is that they originally implemented a feature that would charge you an extra fee when you parked in a Forbidden Zone.

At some later date management demanded a feature where if you park in a designated zone (the green circle) you get a discount, and thus the negative parking fee was born, implemented with virtually no code changes. Note how the title and red "fee" would be better suited to telling me off.

I'd have said they just wanted an excuse to use a not particularly good rhyme. Also, your  image isn't showing for me at all in the post (but I saw it by pasting it into my browser).

It's an HTTP image embed in an HTTPS page, which some browsers are fussy about.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 04 January, 2022, 07:53:06 am
Dunno whether to put this here on in "Grammar..." since it's neither, but only the Graun (yes, I know) could quote a mass in metric then convert it to kilos and get it wrong:

Quote
A meteor that caused an earthshaking boom over suburban Pittsburgh on New Year’s Day exploded in the atmosphere with an energy blast equivalent to an estimated 30 tonnes (27,200kg) of TNT, officials said.

https://www.theguardian.com/science/2022/jan/04/pittsburgh-new-years-day-meteor-explosion-equivalent-to-30-tonnes-of-tnt-says-nasa

You can see how they did it - "oh, we have to write tonnes these days".
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 04 January, 2022, 08:44:52 am
Perhaps it's "autocarrot that makes you cringe".  ;D Similarly, the use of "tonne" rather than "ton" in metaphorical expressions looks wrong to me. "He won tonnes of money on the lottery. She lost her licence after being caught at a tonne on the M5."
Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 04 January, 2022, 09:50:39 am
I expect the Torygraph refuses on principle to use tonnes because they’re
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 04 January, 2022, 12:02:49 pm
She lost her licence after being caught at a tonne on the M5."

This would seem unlikely, as it's within the speed limit  ;)


The use of tonne in metaphorical expressions is probably inevitable when you have Young People who are used to metric.  You hardly ever encounter imperial tons in the real world, so might remain blissfully unaware of the preferred unit for those expressions, perhaps considering it to be a quirk of spelling.  On the plus side, you might have a future career as a copy editor for the Graun.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 04 January, 2022, 12:11:28 pm
In the real world other than the USA, most of the time when you encounter a ton(ne) it's unspecified cos it's either obvious or doesn't really make any difference, seeing as they're so close. I'd be in favour of spelling both versions "ton" cos I don't like the doubled consonant followed by the e (similarly I prefer gram to gramme). When accuracy is needed, use kgs. Or maybe lbs if dealing with Americans.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 04 January, 2022, 12:19:33 pm
In the real world other than the USA, most of the time when you encounter a ton(ne) it's unspecified cos it's either obvious or doesn't really make any difference, seeing as they're so close. I'd be in favour of spelling both versions "ton" cos I don't like the doubled consonant followed by the e (similarly I prefer gram to gramme). When accuracy is needed, use kgs. Or maybe lbs if dealing with Americans.

Agreed, other than a move to change the spelling is going to result in 'mils' style confusion.  But I suppose that's where we are already.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 04 January, 2022, 12:27:34 pm
If you mistake millimetres and thousands of an inch, which I presume is what you're talking about with 'mils', you end up with something seriously the wrong size, whereas if you order two tons of coal and get two tonnes, you won't even notice the difference. And an HGV driver might say they have a 40-ton lorry but I bet they weigh the load in kg. So I don't think it's comparable (unless mils are something completely different to what I think they are).
Title: Re: Arithmetic that makes you cringe
Post by: Arellcat on 04 January, 2022, 01:07:48 pm
She lost her licence after being caught at a tonne on the M5."
This would seem unlikely, as it's within the speed limit  ;)

Given that a hundredweight in the UK was legislated as 112 lbs, I wondered if 'ton' as a colloquialism for 'hundred' came before or after that ruling.  Doing the ton could be 112 mph, so all those café racers cutting down their mudguards and windscreens were all well short.  Interestingly, if doing the ton was 112 km/h, it is very close to 70 mph.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 04 January, 2022, 02:21:12 pm
If you mistake millimetres and thousands of an inch, which I presume is what you're talking about with 'mils', you end up with something seriously the wrong size, whereas if you order two tons of coal and get two tonnes, you won't even notice the difference.

If you were to order two US tons and get two tonnes I'd think you'd be delighted.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 04 January, 2022, 03:00:56 pm
She lost her licence after being caught at a tonne on the M5."
This would seem unlikely, as it's within the speed limit  ;)

Given that a hundredweight in the UK was legislated as 112 lbs, I wondered if 'ton' as a colloquialism for 'hundred' came before or after that ruling.  Doing the ton could be 112 mph, so all those café racers cutting down their mudguards and windscreens were all well short.  Interestingly, if doing the ton was 112 km/h, it is very close to 70 mph.
I'd never thought about linking it with a hundredweight.

If you mistake millimetres and thousands of an inch, which I presume is what you're talking about with 'mils', you end up with something seriously the wrong size, whereas if you order two tons of coal and get two tonnes, you won't even notice the difference.

If you were to order two US tons and get two tonnes I'd think you'd be delighted.
Yep.  :thumbsup:
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 11 January, 2022, 12:37:51 pm
Not really bad arithmetic, but this seems like the appropriate thread for this grumble:

I've noticed a journalistic trend towards the use of kilowatt-hours per year to express power.  I mean, it's a potentially useful unit as a step towards calculating the running costs of a thing, but it's not exactly intuitive.  If you want to impress us with how power-hungry the thing is, use Watts - most people have a sense of what Watts are.  If you want to tell us how expensive it is to run, use the appropriate currency unit.  Otherwise you might as well express it in Pirate-Ninjas.

(I'm suspicious this is due to nobody under the age of 40 having used a 1-bar electric fire.)
Title: Re: Arithmetic that makes you cringe
Post by: mrcharly-YHT on 11 January, 2022, 12:53:36 pm
Not really bad arithmetic, but this seems like the appropriate thread for this grumble:

I've noticed a journalistic trend towards the use of kilowatt-hours per year to express power.  I mean, it's a potentially useful unit as a step towards calculating the running costs of a thing, but it's not exactly intuitive.  If you want to impress us with how power-hungry the thing is, use Watts - most people have a sense of what Watts are.  If you want to tell us how expensive it is to run, use the appropriate currency unit.  Otherwise you might as well express it in Pirate-Ninjas.

(I'm suspicious this is due to nobody under the age of 40 having used a 1-bar electric fire.)
Or a 100W lightbulb.

The persistent use of kW to represent energy is also bloody irritating.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 11 January, 2022, 04:06:04 pm
I expect the use of kW to represent energy is more due to lack of physics but familiarity with electricity bills than unfamiliarity with lightbulbs and similar.

But in similar vein, this is from Bristol Water's snappily titled Watertalk: First there's some talk about washing a single pair of jeans, then:
Quote
An average washing machine uses a titanic 112 litres of water a week. Make sure you fill it up rather than relying on half loads and save yourself a thirst-quenching 10 litres of water each time.
It would be helpful to know how many times a week they reckon an average washing machine is used. I doubt it's as simple as half load saving an actual 50% of the total water use.
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 11 January, 2022, 04:15:22 pm
Quote
An average washing machine uses a titanic 112 litres of water a week. Make sure you fill it up rather than relying on half loads and save yourself a thirst-quenching 10 litres of water each time.
That makes literally no sense.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 11 January, 2022, 04:28:03 pm
The basic reasoning is sound, I think. The average household washes a certain amount of clothes each week. The average washing machine uses a certain amount of water for each wash. Many machines have a 'half-wash' feature which reduces the amount of water used, but it probably doesn't actually halve it. So if you switch the machine on when it's half full and use the half-load feature, you will still be using more water per garment – and thus, over a week in which the same total amount of laundry is done, more water overall – than if you wait till the machine is full and don't use the half-load feature.
Title: Re: Arithmetic that makes you cringe
Post by: mrcharly-YHT on 11 January, 2022, 05:09:26 pm
The basic reasoning is sound, I think. The average household washes a certain amount of clothes each week. The average washing machine uses a certain amount of water for each wash. Many machines have a 'half-wash' feature which reduces the amount of water used, but it probably doesn't actually halve it. So if you switch the machine on when it's half full and use the half-load feature, you will still be using more water per garment – and thus, over a week in which the same total amount of laundry is done, more water overall – than if you wait till the machine is full and don't use the half-load feature.

Except that most modern washing machines automatically adjust how much water they use, according to the load.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 11 January, 2022, 05:42:53 pm
But it's not a straight line relationship with the load. If you run a washing machine completely empty, it will still use some water.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 11 January, 2022, 05:54:19 pm
(I'm suspicious this is due to nobody under the age of 40 having used a 1-bar electric fire.)
Or a 100W lightbulb.

Ohgod, now I feel old.
Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 11 January, 2022, 06:13:40 pm
Not really bad arithmetic, but this seems like the appropriate thread for this grumble:

I've noticed a journalistic trend towards the use of kilowatt-hours per year to express power.  I mean, it's a potentially useful unit as a step towards calculating the running costs of a thing, but it's not exactly intuitive.  If you want to impress us with how power-hungry the thing is, use Watts - most people have a sense of what Watts are.  If you want to tell us how expensive it is to run, use the appropriate currency unit.  Otherwise you might as well express it in Pirate-Ninjas.

(https://46.cdn.ekm.net/ekmps/shops/d4e3f0/images/chris-the-ninja-pirate-plush-toy-29-p.png)

?
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 11 January, 2022, 08:37:23 pm
Nahh, the other kind of Pirate-Ninja: A unit of power equivalent to 1 kilowatt-hour per sol (approximately 40.55W).  It was made up by Andy Weir for his novel, and promptly adopted (in milli-pirate-ninja form) by the Curiosity rover team at JPL.
Title: Re: Arithmetic that makes you cringe
Post by: mrcharly-YHT on 21 February, 2022, 09:15:56 am
I made some biscuits on Sun.

Recipe says 'makes 12 small cookies'

" ... make a 15-20cm long roll . . ."
" ... slice into 5mm - 8mm discs . . ."

That makes 12?
Title: Re: Arithmetic that makes you cringe
Post by: L CC on 21 February, 2022, 12:45:53 pm
That's conversion failure.

15-20cm is 6-8 inches.
5-8mm is half an inch(ish).

Once you start specifying mm for dough you're bound to come a cropper.
Title: Re: Arithmetic that makes you cringe
Post by: mrcharly-YHT on 21 February, 2022, 01:07:18 pm
That's conversion failure.

15-20cm is 6-8 inches.
5-8mm is half an inch(ish).

Once you start specifying mm for dough you're bound to come a cropper.

5-8mm is 1/4inch-ish
Title: Re: Arithmetic that makes you cringe
Post by: L CC on 21 February, 2022, 04:13:39 pm
See, conversion always introduces errors.
Title: Re: Arithmetic that makes you cringe
Post by: mrcharly-YHT on 21 February, 2022, 05:37:44 pm
See, conversion always introduces errors.

Yeah

I suspect you hit nail on head - imperial to metric stuff up.

Recipe made 14 very nice cookies. Trouble is I'm running out already.
Title: Re: Arithmetic that makes you cringe
Post by: Pingu on 17 March, 2022, 05:02:10 pm
Putting it here as I'm guessing it's a conversion error:

https://www.theguardian.com/science/2022/mar/17/nasa-moon-rocket-artemis-florida-cape-kennedy

Quote
...The process of moving the 5.75-million-ton, 32-storey-tall SLS-Orion spacecraft...
Title: Re: Arithmetic that makes you cringe
Post by: ElyDave on 18 March, 2022, 06:10:37 am
In the real world other than the USA, most of the time when you encounter a ton(ne) it's unspecified cos it's either obvious or doesn't really make any difference, seeing as they're so close. I'd be in favour of spelling both versions "ton" cos I don't like the doubled consonant followed by the e (similarly I prefer gram to gramme). When accuracy is needed, use kgs. Or maybe lbs if dealing with Americans.

In some cases it is a very important distinction. In greenhouse gas terms, everything is expressed in tonnes of CO2 equivalent, so a 2000lb ton is a 10% difference vs a 1000kg tonne, and if you then include the GWP factors for non CO2 species, you compound that in absolute terms. Its something that I am constantly on the look out for.

That and other stupid units like cu.ft vs scf vs ncf.

I did ask a bunch of Norwegians which version they were working with, just to be sure, and they looked very confused, not realising that there were different versions available.

Title: Re: Arithmetic that makes you cringe
Post by: cygnet on 18 March, 2022, 09:28:23 pm
Putting it here as I'm guessing it's a conversion error:

https://www.theguardian.com/science/2022/mar/17/nasa-moon-rocket-artemis-florida-cape-kennedy

Quote
...The process of moving the 5.75-million-ton, 32-storey-tall SLS-Orion spacecraft...

Quote from: the granuad
This article was amended on 18th March

I'm struggling to think of a conversion that would get  "one" from 2600t to 5.6Mt (or T depending on what ElyDave said)
It's not just one order or magnitude out...

But at least they had the decency to correct? and acknowledge the change.

Still looking at you BBC and you Institution of Civil Engineers for some glaring numerical errors.
Title: Re: Arithmetic that makes you cringe
Post by: jsabine on 18 March, 2022, 10:52:57 pm
I'm struggling to think of a conversion that would get  "one" from 2600t to 5.6Mt (or T depending on what ElyDave said)
It's not just one order or magnitude out...

Lb to kg to ton(ne)s (or vice versa), a rounding error, and missing out a stage?

5600lb is 2540kg, 2600kg is 5732lb, so numbers above 2551(kg=5624lb) or below 5649(lb=2562kg) get us there.

(ETA - And I've just read the Guardian's correction, and reread Pingu's post, and it was 5.75 million tons. 5750lb is 2608kg. I bet the NASA press release says 5,750,000lb.)

(ETFA - That Guardian/Reuters story was published on 17th March, before the rocket's rollout began. The only press release directly on the rollout that's currently available on the NASA website is from 18th March, after the rollout had completed successfully. It gives the weight as 3.5 million lbs. That's not 2,600 tons.

However, a press release the day before says that once the rocket had been rolled out, they'll fuel it with 700,000 gallons of propellant (liquid hydrogen and oxygen). 700,000 US gallons is 2,649,788 litres.

While liquid oxygen is a bit denser than water, and liquid hydrogen is a lot less dense, what's the reckoning a time-pressed journo figured 'hey, a litre's a kilo,' rounded it to 2,600 tons, and missed the fact that's the weight of the fuel, not the weight of the rocket?)

(ETFFA - There's a Feb 3rd press release that says the rocket's weight is 5.75 million lb. FFS.)
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 04 April, 2022, 04:59:09 pm
Quote
Contract soldiers (who sign up for a period of three years) are paid 200% less than US counterparts, at about US$1,000 (£760) a month,
200% less? Isn't that a negative number?
Title: Re: Arithmetic that makes you cringe
Post by: Salvatore on 08 April, 2022, 12:37:50 pm
At the risk of alienating and enraging people who refuse to click on links to twitter, I present this thread for your amusement

https://twitter.com/darachos/status/1512312741264080899

In unrelated news, last month I was invited for an AAA screening, "offered free of charge to all men in their 65th year". Given that I turned 65 7 months ago, I'm now in my 66th year. Does that mean I'll have to pay?

See also reporting of incidents in football matches, where "in the 21st minute" is synonymous with "after 21 minutes". Or "on 21 minutes" which is as far as I know is unique to football reportage.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 08 April, 2022, 01:01:48 pm
In unrelated news, last month I was invited for an AAA screening, "offered free of charge to all men in their 65th year". Given that I turned 65 7 months ago, I'm now in my 66th year. Does that mean I'll have to pay?

See also reporting of incidents in football matches, where "in the 21st minute" is synonymous with "after 21 minutes". Or "on 21 minutes" which is as far as I know is unique to football reportage.

"There are two hard things in computer science: cache invalidation, naming things, and off-by-one errors."

I have sympathy for this when applied to time periods, because it's the sort of thing that you get more wrong the more you think about it, until you reach true enlightenment.  It doesn't help that people (well, normal people) don't like to start counting from zero, which makes the language wooly: I'd make distinction between "the 21st minute" and "minute 21", but I suspect most people wouldn't.  I expect someone re-phrased "65 years old" to "in their 65th year" in an attempt to avoid an implied equal-to-or-greater-than...

The football convention is weird, though.
Title: Re: Arithmetic that makes you cringe
Post by: Pingu on 08 April, 2022, 06:16:41 pm
AAAs with no charge are not much use, thobut.
Title: Re: Arithmetic that makes you cringe
Post by: Salvatore on 08 April, 2022, 09:13:47 pm
AAAs with no charge are not much use, thobut.
I see what you did there.

The screening was this morning and there is no sign of an A on my AA.
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 13 April, 2022, 04:49:30 pm
From today's official Coronavirus stats…

Quote
A confirmed case is someone who has tested positive for coronavirus.

Between 7 April 2022 and 13 April 2022, 253,456 people had a confirmed positive test result. This shows a decrease of -34.9% compared to the previous 7 days.


My bold. A decrease with a negative sign.

GGGGGRRRR!
Title: Re: Arithmetic that makes you cringe
Post by: ElyDave on 14 April, 2022, 06:43:54 am
So the number went up?
 ??? ???
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 15 April, 2022, 10:07:57 pm
I think the number went down but…

Double negatives AAAAARRRRRGGGGGHHHHH!
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 16 April, 2022, 09:57:22 am
I think they consider a double negative as being, like, y'know, very negative.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 16 April, 2022, 10:57:32 am
Well, it's certainly a no-no (does that make it yes?).
Title: Re: Arithmetic that makes you cringe
Post by: rafletcher on 22 April, 2022, 11:19:44 am
Yodel tracking site today.

You driver is making stop 40 of 151.

Stops before you 116.

ETA: We were 156 of 151. I can only conjecture 5 deliveries were cancelled or deferred.

Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 22 April, 2022, 11:27:29 am
“Stops before you: 13” said Yodel when I prodded F5 yesterday arvo.  Ten seconds later the doorbell was rung by the Yodelling Hoover Driver with my new Shiny clutched in his paw.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 22 April, 2022, 11:52:50 pm
“Stops before you: 13” said Yodel when I prodded F5 yesterday arvo.  Ten seconds later the doorbell was rung by the Yodelling Hoover Driver with my new Shiny clutched in his paw.

I think we've concluded those things are a work of fiction, if only for data protection reasons.
Title: Re: Arithmetic that makes you cringe
Post by: Pickled Onion on 23 April, 2022, 02:45:51 pm
I was intrigued why my broadband bill is 1p over this month.

I pay £28 a month which is £23.33 plus £4.67 VAT = £28

This time I got a two month bill and it turns out the actual price is £23.33333333333... etc so two of those, rounded comes to £46.67

But hang on, that shouldn't matter, because 20% of £46.67 is £9.33 so all should be good. Ah but no, that's not what they've done. Although they billed the base price of two times the unrounded figure, the VAT is two times the rounded VAT = £9.34

Now 1p is neither here nor there, but over, say, a million customers that's £10,000 and it certainly won't go to HMRC. One has to wonder if the odd choice of different rounding on two rows of the bill wasn't deliberate.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 14 June, 2022, 09:25:45 am
Now, not sure what was meant by this or even if I heard correctly: Springwatch, Megan in Newcastle, aprox. 'gardens in Newcastle have a total area greater than all of the National Parks put together' (very rough paraphrase). Now, The Lake District is quite close to the total area of Newcastle Metropolitan Borough and Greater London.
Possibly it should be more than the total area of gardens in the Parks, as some of the parks have lots of non-garden.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 05 September, 2022, 04:09:33 pm
Pick the bones out of an article about ants, insulin, and longevity:

"Anti-insulin protein helps queen ants live five times longer than workers " fair enough.

"...alongside this reproductive transition is a dramatic 500% increase in lifespan." so, 6x the life.

"...tend to live for between four and five years, while workers barely last longer than seven months." approx. 7 - 8½x as long.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 05 September, 2022, 04:20:24 pm
When does an ant's life begin anyway? When the egg is laid? When it hatches as a larva? When it emerges from the pupa as a adult ant? And at what point does the differentiation between queen and worker happen? This (https://askabiologist.asu.edu/individual-life-cycle) suggests the queen/worker distinction begins as larvae, but it's not clear from that whether the pupae are distinct or only the adults. It also says queens can live "for decades under the right conditions" so could be 20 or more times the lifespan of a worker.
Title: Re: Arithmetic that makes you cringe
Post by: Pickled Onion on 05 September, 2022, 07:19:55 pm
Not arithmetic, but I couldn't find a numeracy that makes you cringe thread

Quote from: Caroline Nicholls on R4 news
... and against the Euro, Sterling is trading at one Euro point one hundred and fifty-nine cents...
Title: Re: Arithmetic that makes you cringe
Post by: Diver300 on 26 September, 2022, 07:12:23 pm
From:-https://www.purpleparking.com/airport-parking/london-heathrow/purple-parking-heathrow-terminal-2-terminal-3 (https://www.purpleparking.com/airport-parking/london-heathrow/purple-parking-heathrow-terminal-2-terminal-3)

Quote
The maximum length for vehicles is 2.15 metres

I feel that restricting parking to vehicles significantly shorter than a Smart car 2 seater may leave them limited clientele.
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 26 September, 2022, 07:37:59 pm
Not arithmetic, but I couldn't find a numeracy that makes you cringe thread

Quote from: Caroline Nicholls on R4 news
... and against the Euro, Sterling is trading at one Euro point one hundred and fifty-nine cents...

I was disappointed with the latest Arrivée and its 'LEL Volunteer Heroes Page08' cover...
Title: Re: Arithmetic that makes you cringe
Post by: Pingu on 16 October, 2022, 05:49:39 pm
Quote
Julio Loace was 24 when, in the summer of 1962... Loace, now 86...

https://www.theguardian.com/world/2022/oct/16/cuban-missile-crisis-60-years-on-russians
Title: Re: Arithmetic that makes you cringe
Post by: Mrs Pingu on 16 October, 2022, 06:30:43 pm
I watched a colleague the other day, clever man, scientist, probably has a doctorate, working out percent on a calculator and still needing to do the x100 step at the end.
Title: Re: Arithmetic that makes you cringe
Post by: mark on 16 October, 2022, 07:07:07 pm
Quote
Julio Loace was 24 when, in the summer of 1962... Loace, now 86...

https://www.theguardian.com/world/2022/oct/16/cuban-missile-crisis-60-years-on-russians

Excellent article, even if the writer can't add or subtract very well.
Title: Re: Arithmetic that makes you cringe
Post by: ian on 19 October, 2022, 12:21:55 pm
I watched a colleague the other day, clever man, scientist, probably has a doctorate, working out percent on a calculator and still needing to do the x100 step at the end.

That's me, that is.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 19 October, 2022, 01:28:11 pm
A chum of MrsT taking a new first-year science class set them a standard arithmetic test.  One of them got 20/20, a few got 12-14, the rest got less than 10 and a few 0.  Typical question: How many hours in 900 minutes?  That's the kind of question we got fired at us in primary school when I was 9.

I can remember laughing on hearing that first-year physics for medical students in Edinburgh started by defining sin, cos & tan, but that? No wonder she can't wait for the holidays.
Title: Re: Arithmetic that makes you cringe
Post by: hatler on 19 October, 2022, 01:34:52 pm
First year ?   What age are the students ?
Title: Re: Arithmetic that makes you cringe
Post by: ian on 19 October, 2022, 01:45:07 pm
I can't really do maths. I got to sit in the corridor because of my thorough disengagement with the process of learning my times-tables. As mentioned, I never learned long division, quite honestly short was taxing enough not to bother with. I mean, if there's an apocalypse that involves all the world's calculators ceasing to work, and the only way to fight off the resulting zombie hoards is through quick fire square roots, I'm screwed.

It's a chance I'm willing to take.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 19 October, 2022, 01:58:27 pm
First year ?   What age are the students ?

Post-Bac would make them around 18.  The problem for French universities is that anyone who gets their Bac is entitled to a place, and selection takes place at the end of first year once the poor lecturers and tutors are shaking with nerves and popping antacids for their ulcers.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 03 November, 2022, 08:40:52 am
review of a watch: "Beating at a frequency of four Hz (28,800 beats per hour)..."
Title: Re: Arithmetic that makes you cringe
Post by: Slave To The Viking on 11 November, 2022, 07:37:13 am
review of a watch: "Beating at a frequency of four Hz (28,800 beats per hour)..."

Ooooh, that Hertz.
Title: Re: Arithmetic that makes you cringe
Post by: mrcharly-YHT on 16 November, 2022, 04:01:39 pm
"Mix .... with 4 gallons (16l) of water"


FFS
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 16 November, 2022, 04:16:43 pm
Seems accurate enough for round numbers, unless it's specifically UK gallons.
Title: Re: Arithmetic that makes you cringe
Post by: mark on 16 November, 2022, 04:40:05 pm
4 US gallons = 15.1 liters
4 UK gallons = 18.2 liters
Not really accurate, even for round numbers.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 16 November, 2022, 04:47:16 pm
What are those quantities in litres?
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 16 November, 2022, 06:43:51 pm
16 litres is just over 3.5 US gallons and just over 4 UK gallons, so if they can't be bothered to specify which they're referring to and whatever this substance is doesn't need to be mixed particularly accurately (which is hopefully the case, because if it does need to be accurate someone's bound to use the wrong gallons), 4 would be the most appropriate or least inaccurate whole number of gallons to give. Probably.
Title: Re: Arithmetic that makes you cringe
Post by: JonBuoy on 16 November, 2022, 07:08:53 pm
16 litres is just over 3.5 US gallons and just over 4 UK gallons, so if they can't be bothered to specify which they're referring to and whatever this substance is doesn't need to be mixed particularly accurately (which is hopefully the case, because if it does need to be accurate someone's bound to use the wrong gallons), 4 would be the most appropriate or least inaccurate whole number of gallons to give. Probably.

Erm...is this a special performance for this particular thread?
Title: Re: Arithmetic that makes you cringe
Post by: Lightning Phil on 16 November, 2022, 07:14:18 pm
16 litres is just over 3.5 US gallons and just over 4 UK gallons, so if they can't be bothered to specify which they're referring to and whatever this substance is doesn't need to be mixed particularly accurately (which is hopefully the case, because if it does need to be accurate someone's bound to use the wrong gallons), 4 would be the most appropriate or least inaccurate whole number of gallons to give. Probably.

You are certainly making us cringe with your arithmetic for UK litres
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 16 November, 2022, 07:26:35 pm
Bah! Other way round of course. 3.5 UK gallons and 4.2 US gallons. Or 66.6 recurring "legal cups" which sounds like something covered under "Rule 34".
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 01 December, 2022, 08:37:27 am
Article in the Grauniad about storage of gas under the North Sea:
"A 30km-square reservoir under sandstone, it is twice the size of Lake Windemere."

Windermere is 14.73 sq. km., so rather less than 900 of 'em - or possibly the G has got it wrong yet again.
Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 01 December, 2022, 10:23:29 am
The only confusion between x km square and x km2 innit.  Words rather than maths.
Title: Re: Arithmetic that makes you cringe
Post by: ian on 01 December, 2022, 11:02:35 am
The only confusion between x km square and x km2 innit.  Words rather than maths.

This is why scientists can never decorate a room.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 01 December, 2022, 05:29:16 pm
A 30 km square isn't ambiguous, of course. 30 km squared I do find somewhat ambiguous and much prefer 30 square km - 30 of 1 km*1 km.
Title: Re: Arithmetic that makes you cringe
Post by: Diver300 on 01 December, 2022, 09:44:53 pm
From here:- https://aecramtrucks.com/trx/ (https://aecramtrucks.com/trx/)
which says that a 6.2 litre engine, supercharged to 0.76 bar, turning at over 5000 rpm, uses up to 32.9 litres of air a minute.

The actual figure is either 32.9 m3 or 32.9 kg, I'm not sure which.
Title: Re: Arithmetic that makes you cringe
Post by: cygnet on 01 December, 2022, 09:49:35 pm
The only confusion between x km square and x km2 innit.  Words rather than maths.

This is why scientists can never decorate a room.

I'm sure scientists could order the required amount of paint/wallpaper/flooring. I'm less sure about journalists.
Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 02 December, 2022, 12:54:37 pm
Not arithmetic as such, but I found this on an article about Presta vs Schraeder valves

Quote
Your average valve will be between 5-10cm (1.96-3.92″) long

1. Umm, no they're not.
2. Who measures bike valves to the nearest ten thousandths of an inch?  No one, that's who. Over precise conversions. I hate them.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 02 December, 2022, 01:02:06 pm
Over precise unit conversions perform the useful function of indicating which unit is more trustworthy.
Title: Re: Arithmetic that makes you cringe
Post by: Bledlow on 05 December, 2022, 07:59:50 pm
Not arithmetic as such, but I found this on an article about Presta vs Schraeder valves

Quote
Your average valve will be between 5-10cm (1.96-3.92″) long

1. Umm, no they're not.
2. Who measures bike valves to the nearest ten thousandths of an inch?  No one, that's who. Over precise conversions. I hate them.
When I visited Sri Lanka I noticed that railway stations had their height above sea level on their name boards.

They were in multiples of 3.05 metres.  :facepalm:
Title: Re: Arithmetic that makes you cringe
Post by: Slave To The Viking on 05 December, 2022, 09:01:41 pm
Not arithmetic as such, but I found this on an article about Presta vs Schraeder valves

Quote
Your average valve will be between 5-10cm (1.96-3.92″) long

1. Umm, no they're not.
2. Who measures bike valves to the nearest ten thousandths of an inch?  No one, that's who. Over precise conversions. I hate them.

Ten thousandths?
Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 05 December, 2022, 09:11:58 pm
Not arithmetic as such, but I found this on an article about Presta vs Schraeder valves

Quote
Your average valve will be between 5-10cm (1.96-3.92″) long

1. Umm, no they're not.
2. Who measures bike valves to the nearest ten thousandths of an inch?  No one, that's who. Over precise conversions. I hate them.

Ten thousandths?
I think it's to the nearest ten thousandths. 3.92 inches is three inches nine hundred and twenty thousandths isn't it? Not "tenths" wot is tenths of a thousandth. Or 0.000n inches. I could be wrong though.
Title: Re: Arithmetic that makes you cringe
Post by: Slave To The Viking on 07 December, 2022, 05:24:14 pm
Not arithmetic as such, but I found this on an article about Presta vs Schraeder valves

Quote
Your average valve will be between 5-10cm (1.96-3.92″) long

1. Umm, no they're not.
2. Who measures bike valves to the nearest ten thousandths of an inch?  No one, that's who. Over precise conversions. I hate them.

Ten thousandths?
I think it's to the nearest ten thousandths. 3.92 inches is three inches nine hundred and twenty thousandths isn't it? Not "tenths" wot is tenths of a thousandth. Or 0.000n inches. I could be wrong though.

Oh...I see. So 'hundredths' then?! But odd to invoke a decimal place that isn't displayed.
Title: Re: Arithmetic that makes you cringe
Post by: Pickled Onion on 07 December, 2022, 08:45:32 pm
The "thou" was a standard fractional quantity of an inch, once you'd run beyond the usual halving - thirty-seconds, sixty-fourths, thousandths. It fits well with the 1000 multipliers/divisors of SI units used properly/scientifically. Also hundredths not being much use over sixty-fourths.
Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 07 December, 2022, 11:32:40 pm
In a workshop the apprentice was being put through his paces:
"Now lad, how many eighths in an inch?"
"Eight boss"
"And how many sixteenths?"
He thinks for bit
"Sixteen?"
"Good lad, how about sixty fourths?"
He thinks a bit longer.
"Sixty four"
"Right enough. Now how many thou?"
"Blimey guvnor, there must be millions of 'em"
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 08 December, 2022, 11:10:56 am
When I visited Sri Lanka I noticed that railway stations had their height above sea level on their name boards.

They were in multiples of 3.05 metres.  :facepalm:
Hot-rolled steel Universal Beam sizes are in metric-equivalent-to-imperial sizes:
178mm x 102mm ~ 7" x 4"
203mm x 133mm ~ 8" x 5 1/4"
254mm x 146mm ~ 10" x 5 3/4"
305mm x 165mm ~ 12" x 6 1/2"
610mm x 229mm ~ 24" x 9"
etc etc
Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 08 December, 2022, 01:02:06 pm
Similarly diamond drill core bits come (or came, I think they've got a bit better now) in strange numbers of millimetres. Which by huge coincidence weere nice round* inch numbers.


*hopefully they drill nice round holes.
Title: Re: Arithmetic that makes you cringe
Post by: mrcharly-YHT on 08 December, 2022, 01:37:25 pm
https://www.bbc.com/news/world-asia-63903771 (https://www.bbc.com/news/world-asia-63903771)

Quote
Currently, the most widely used calculation method in Korea is the so-called "Korean age system", in which a person is one year old at birth and then gains a year on the first day of each new year

My brain is a bit fuzzy, but I strongly suspect they've got this the wrong way round:


Quote
This means that, for example, as of 8 December 2022, a person born on December 31 2002 is 19 under the Korean age system, 20 under the international system and 21 under the counting system.
Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 08 December, 2022, 06:13:40 pm
Isn’t that what they do with racehorses?
Title: Re: Arithmetic that makes you cringe
Post by: mrcharly-YHT on 11 December, 2022, 06:43:31 pm
Horses all have the same 'birthday', but it counts from zero, so a foal is 0 years, x months old. Then they become a yearling - one year old, etc.
Title: Re: Arithmetic that makes you cringe
Post by: Andy W on 12 December, 2022, 06:17:58 am
And not forgetting 254 x 254 steel beam is 10" x10" weighs a tonne or ton certainly not a tun
Title: Re: Arithmetic that makes you cringe
Post by: cygnet on 12 December, 2022, 08:40:56 pm
When I visited Sri Lanka I noticed that railway stations had their height above sea level on their name boards.

They were in multiples of 3.05 metres.  :facepalm:
Hot-rolled steel Universal Beam sizes are in metric-equivalent-to-imperial sizes:
178mm x 102mm ~ 7" x 4"
203mm x 133mm ~ 8" x 5 1/4"
254mm x 146mm ~ 10" x 5 3/4"
305mm x 165mm ~ 12" x 6 1/2"
610mm x 229mm ~ 24" x 9"
etc etc

The nominal size can present problems for the unwary - to get different weights of the same beams the rolling mills use the same internal rollers and vary the spacing of the edges/top and bottom. E.g. a 610UB can vary in depth by 40mm depending on the weight specified.
And not forgetting 254 x 254 steel beam is 10" x10" weighs a tonne or ton certainly not a tun
An actual 10" x10" UC weighs 73kg/m so that's a very long and very slender beam. The "heaviest" 254UC is 167kg/m and is about 11 3/8" deep

Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 07 January, 2023, 09:13:52 am
A conversion error,so probably closer tto translation than arithmetic .  Anyway, from a recipe:

Quote
. It should be about 1cm/¼in thick.

Butter a 1.5 litre/2 pint 12¾fl oz pudding basin and line it with the pastry.
A quarter of an inch is much closer to half a centimetre
1.5l is 2.6 pints
12.75 floz aint even a pint.

Title: Re: Arithmetic that makes you cringe
Post by: hatler on 07 January, 2023, 09:19:03 am
But isn't 2 pints plus 12.75 fl oz about 2.6 pints ?
Title: Re: Arithmetic that makes you cringe
Post by: hatler on 07 January, 2023, 09:19:46 am
2 pints and 12 fl oz of course would have been spot on.
Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 07 January, 2023, 10:02:08 am
Ah,yes, gotcha. Note to self, read question fully (just had an online test for work purposes. Thankfully read those questions fully and passed).

Meanwhile, my pudding bowl is too small.
Title: Re: Arithmetic that makes you cringe
Post by: Pickled Onion on 09 January, 2023, 06:55:19 pm
I can just imagine going into a shop and asking for a "2 pint 12¾fl oz pudding basin"  ::-)
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 12 February, 2023, 06:37:43 pm
Not exactly arithmetic but:
Quote
Great Avon Wood will be located near Pensford, a few miles south of Bristol, and will be the size of Winnie-the-Pooh’s Hundred Acre Wood.
So what's that in acres?
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 14 February, 2023, 04:57:39 pm
Sort of arithmetic:
on Driving Licence, get eyes tested at least every 2 years, so I'm OK at about 5 - 6 years because that's more than 2 years.
A bit similar on a bus route (BC , of course)claiming a bus at least every 30 minutes. As it had a 6-hour overnight gap and early and late were hourly, it was accurate.
On a van that repaired pumping equipment, ETA 1 hour nationwide. That's not ETA - it's ET to A.
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 22 February, 2023, 07:47:31 pm
North West London Waste Authority had this phrase in its ad on Facebook.

HTF can you compare a weight/mass with a length?

Quote
Londoners - did you know that we produce 2 million tonnes of waste every year? 🗑️
That's more than the entire length of the River Thames!
Title: Re: Arithmetic that makes you cringe
Post by: Pingu on 22 February, 2023, 11:42:27 pm
North West London Waste Authority had this phrase in its ad on Facebook.

HTF can you compare a weight/mass with a length?

Quote
Londoners - did you know that we produce 2 million tonnes of waste every year? 🗑️
That's more than the entire length of the River Thames!

 :thumbsup:
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 23 February, 2023, 01:07:47 am
I suppose in theory you could add up the mass of all the water in it.  But that's the sort of woolly numerical integration problem that you can be pretty sure they weren't thinking of at the time.

Maybe they're counting in double-decker buses bin lorries?
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 23 February, 2023, 11:03:05 am
Mass of water is what it made me think of. The Thames is 346km long according to the internet, so if it averages 2m deep and 3m wide, that comes to about 2 million tonnes of water. Obviously it's a lot deeper and wider than that by the time it reaches London, but does it have sufficient little-streamy length to bring the average down to those figures? I've no idea.

Or they could mean that if they buried it all in a trench of unstated width and depth, it would be longer than the Thames.

Most likely they just wanted to pick a London-related large thing. Next time, it might be "n times bigger than Hyde Park".

In fact, a lot of North West London waste goes to Bristol. To be precise, there's a daily train, known as the binliner, which takes it to a CPH incinerator in Avonmouth every morning and takes the empty containers back each evening. It passes through my local station about 8.30pm and even though it's empty, it stinks. I suppose I should be glad I'm never up early enough to smell the full one!
Title: Re: Arithmetic that makes you cringe
Post by: Jasmine on 23 February, 2023, 01:36:54 pm
I think they mean "That's more than enough to fill the entire length of the River Thames", meaning that if you just tipped it in the river it would completely fill it.
Title: Re: Arithmetic that makes you cringe
Post by: Jaded on 23 February, 2023, 01:41:47 pm
I think they mean "That's more than enough to fill the entire length of the River Thames", meaning that if you just tipped it in the river it would completely fill it.

And of course, this is what several Water Companies are trying to do.
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 23 February, 2023, 07:24:13 pm
I suppose I should be glad I'm never up early enough to smell the full one!

The full ones might be less stinky than the empty ones on account of having less space in which to circulate StinkyGas…

… Just a thought.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 23 February, 2023, 08:18:19 pm
I suppose I should be glad I'm never up early enough to smell the full one!

The full ones might be less stinky than the empty ones on account of having less space in which to circulate StinkyGas…

… Just a thought.
I can kind of see how that might apply if you were in the container (the rubbish is transported in shipping containers) but as this is a moving train, I'm not getting closer to it than standing on a platform (behind the yellow line of course!) as it passes.
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 09 March, 2023, 01:51:07 am
https://www.standard.co.uk/news/crime/driver-speeding-a40-westway-london-galicia-b1065631.html?itm_source=Internal&itm_channel=homepage_trending_article_component&itm_campaign=trending_section&itm_content=4 (https://www.standard.co.uk/news/crime/driver-speeding-a40-westway-london-galicia-b1065631.html?itm_source=Internal&itm_channel=homepage_trending_article_component&itm_campaign=trending_section&itm_content=4)

22 x 3 + 7 does not equal 81...
Title: Re: Arithmetic that makes you cringe
Post by: lissotriton on 09 March, 2023, 02:27:04 am
https://www.standard.co.uk/news/crime/driver-speeding-a40-westway-london-galicia-b1065631.html?itm_source=Internal&itm_channel=homepage_trending_article_component&itm_campaign=trending_section&itm_content=4 (https://www.standard.co.uk/news/crime/driver-speeding-a40-westway-london-galicia-b1065631.html?itm_source=Internal&itm_channel=homepage_trending_article_component&itm_campaign=trending_section&itm_content=4)

22 x 3 + 7 does not equal 81...
Speeding can be between 3 and 6 points, depends on how much exceed the speed limit by.
And I'm not sure if that 81 includes the 7 points he already had.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 19 April, 2023, 08:42:19 am
Googling a conversion just now, this wonder appeared in the "questions asked" list further down the page:

How many pounds is 70kg in stones?
Title: Re: Arithmetic that makes you cringe
Post by: geoff on 19 April, 2023, 03:44:39 pm
Googling a conversion just now, this wonder appeared in the "questions asked" list further down the page:

How many pounds is 70kg in stones?
I have a feeling it might be 11

Sent from my Pixel 6a using Tapatalk

Title: Re: Arithmetic that makes you cringe
Post by: HTFB on 19 April, 2023, 04:32:04 pm
5kg = 11 lb, almost bang on. So 70kg = 154lb = 11st.

The question almost makes sense, if "70kg in stones" could mean "rounded to the nearest stone" and you also don't know how many pounds a stone is.
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 24 April, 2023, 10:24:25 am
https://www.bbc.co.uk/news/uk-england-london-65354929 (https://www.bbc.co.uk/news/uk-england-london-65354929)

Quote
A First Folio edition of William Shakespeare's plays that was published in 1623 is being put on display.

Guildhall Library will be showcasing the rare book as part of a celebration of 400 years since the playwright's birth.

Published seven years after the Bard's death, the book contains all of his plays.

It's quite well known that Shakespeare died on his birthday, but I didn't know that he was -7 years old at the time.

Title: Re: Arithmetic that makes you cringe
Post by: Pickled Onion on 03 June, 2023, 05:39:09 pm
Guardian really going for it in today's print version:

Quote
... temperatures will breach a global annual average temperature of 1.5C (34.7F) above pre-industrial levels

A quick google shows they made the exact same mistake (https://www.theguardian.com/environment/2020/jan/13/un-draft-plan-sets-2030-target-to-avert-earths-sixth-mass-extinction-aoe) back in January.

It gets worse

Quote
... the extra warming that comes with El Niño events will temporally push the global climate over 1.5C. The temperature may then drop back below 1.5C, allowing climate change deniers to tell everyone the world is now cooling

Certainly if the temperature drops below 1.5C that would be quite something, given it's around 14C. Extra points for not being able to spell temporarily.

ETA The online version corrects the second but not the first
Title: Re: Arithmetic that makes you cringe
Post by: mrcharly-YHT on 20 June, 2023, 12:38:53 pm
Quote
For more regular running the watch consumed around 6-7% of the battery in 80 minutes with its default automatic GPS mode without music or 12% with offline music from Spotify. That’s works out to at least 22 hours of high-precision tracking, which is certainly long enough for most activities.

So it uses 12% in 80 min. I make that a battery life of 11 hours.

'At least' 22 hours should maybe be 'at most' 22hours, if you don't listen to music.
Title: Re: Arithmetic that makes you cringe
Post by: Pingu on 28 June, 2023, 09:27:08 pm
It's great when units are a mixture of imperial and metric  :hand:

Quote
10.5 litres of water per mile of pipe...per minute

https://www.theguardian.com/environment/ng-interactive/2022/dec/01/down-the-drain-how-billions-of-pounds-are-sucked-out-of-englands-water-system
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 18 July, 2023, 05:51:41 pm
Sports commentator (can't recall the exact wording) re. pole vault: ...of 6", 10cm. Woman, so probably been told it's 6" before.
Title: Re: Arithmetic that makes you cringe
Post by: Tim Hall on 18 July, 2023, 06:49:06 pm
Arithmetic or Bad Science, or just Not Understanding:

The other day I caught part of a documentary series on Radio 4 about the history of textiles.  Thee was a bit about textiles in sport where they mentioned Roger Bannister's lightweight running spikes he used for his sub 4 minute mile. The weight was given as 127.6 grammes. Which struck me as remarkably precise.  Have you seen felt how small a tenth of a gramme is? Putting 127.6g into any online converter gives 4.5 ounces, a much more believable figure. BBC not understanding precision and convesrion again.
Title: Re: Arithmetic that makes you cringe
Post by: Pickled Onion on 18 July, 2023, 09:58:53 pm
Arithmetic or Bad Science, or just Not Understanding:

All of those, plus poor education. I remember the physics master drumming into us from day 1 that you can never have more significant figures in the result of a calculation than the least precise of the input figures. So unless that was 4.500 oz. the figure in grams is just not correct. Anyone flouting that rule got zero marks, we soon learnt.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 18 July, 2023, 10:01:45 pm
Can I nominate all the BHPC racers who demonstrated an inability to count to four at the weekend?

Next time we do a fixed-laps race, I'm going to get Barney to read from the Book of Armaments on the start line.
Title: Re: Arithmetic that makes you cringe
Post by: Mr Larrington on 18 July, 2023, 11:30:34 pm
'twas ever thus. Running gag in the 1980s:

Omnes: How many fingers am I holding up, Andy?

A Pegg: Thursday!
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 18 July, 2023, 11:34:43 pm
Yes, I'm reliably informed that the whole reason for having a jam-filled Babbage-engine is that it's better[1] at counting laps than the average BHPC racer.  Good to have that confirmed.


[1] In a specific and limited way.
Title: Re: Arithmetic that makes you cringe
Post by: Poacher on 28 July, 2023, 09:15:50 am
Straightforward one from Freeview's blurb on last night's "Shipwrecks: Britain's Sunken History".
"The terrible toll taken by shipwrecks was such that in the winter of 1820 some 20,000 seaman lost their lives in the North Sea alone. That's 20 jumbo jets."
Where are these 1,000 passenger capacity jumbos, or was an assumption made about ground casualties?
Title: Re: Arithmetic that makes you cringe
Post by: rafletcher on 28 July, 2023, 10:18:19 am
Though correct, I bridle at "dozens" being used to describe 25.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 22 August, 2023, 08:10:16 am
Article in BBC Science focus:
"How does the Earth cooling down affect the inner core?

This process adds 8,000 tonnes of iron to the inner core every second – the equivalent of the mass of the entire human population added daily."

C'mmon! - that's the mass of a Usanian trolley bus when full.
Title: Re: Arithmetic that makes you cringe
Post by: L CC on 22 August, 2023, 08:51:22 am
8,000 tonnes/sec
28.8 million tonnes per hour
691.2million tonnes per day

world population=8 billion
averaging 70kg (lots of those 8bn are children)
= 560 million tonnes

I think their maths is sound.

Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 22 August, 2023, 12:11:30 pm
Quote
Paired with brown rice, avocado and indecent amounts of lime, black beans work splendidly in a balanced, almost five-ingredient lunch.
So why not just call it four ingredients?
Title: Re: Arithmetic that makes you cringe
Post by: Legs on 22 August, 2023, 01:41:07 pm
Also playing fast 'n' loose with the conventional meaning of 'paired' there, Cudzo...
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 03 October, 2023, 07:44:41 pm
The Graun:
Quote
It’s Conservative conference time again, which means listening to multiple politicians make cringe speeches while jostling for position; fringe events that undermine everything going on in the main hall; and, this year, the probable scrapping of a £100bn infrastructure project that directly benefits the city they are in. If HS2 ends up as a train from Old Oak Common to Birmingham, Sunak should pay for it himself, or at least the three-quarters he could afford.
There's a link in there to this: https://www.politics.co.uk/reference/rishi-sunak-net-worth-2/
which tells us Sunak has £730 million...
Title: Re: Arithmetic that makes you cringe
Post by: Pickled Onion on 03 October, 2023, 08:19:56 pm
Oh come on, what's a couple of orders of magnitude between friends? "the three-quarters of one percent he could afford" doesn't sound nearly as good.
Title: Re: Arithmetic that makes you cringe
Post by: cygnet on 03 October, 2023, 08:56:40 pm
Quote
Paired with brown rice, avocado and indecent amounts of lime, black beans work splendidly in a balanced, almost five-ingredient lunch.
So why not just call it four ingredients?

Isnt that a "Vege" burrito minus the tortilla?
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 22 October, 2023, 01:48:58 pm
Presentation of numbers: "Our revenue moved from two billion five hundred and eighteen to three billion and seventy-five"

would suggest to me 2.518 billion to 3.75 billion. The accompanying chart makes clear it's actually 3.075 billion. But the speaker is French (presenting in English) so il faut couper some slack, n'est ce pas-innit.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 22 October, 2023, 01:49:37 pm
Quote
Paired with brown rice, avocado and indecent amounts of lime, black beans work splendidly in a balanced, almost five-ingredient lunch.
So why not just call it four ingredients?

Isnt that a "Vege" burrito minus the tortilla?
Burrito minus tortilla equals risotto!
Title: Re: Arithmetic that makes you cringe
Post by: Pickled Onion on 22 October, 2023, 04:47:11 pm
Presentation of numbers: "Our revenue moved from two billion five hundred and eighteen to three billion and seventy-five"

would suggest to me 2.518 billion to 3.75 billion. The accompanying chart makes clear it's actually 3.075 billion. But the speaker is French (presenting in English) so il faut couper some slack, n'est ce pas-innit.

I initially read it as the second - 3.075 billion - assuming they'd missed out the word million, twice. But it's unclear.

Without the word "revenue", I'd read it as a scientist and assume the numbers were 2,000,000,518 and 3,000,000,075.

They've also made the cardinal sin of missing the units (unless that's your crop). Dollars or Euros neither here nor there nowadays, but if it's Yen...
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 22 October, 2023, 05:52:57 pm
The units were specified on the accompanying graph but not in the spoken presentation.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 26 November, 2023, 06:17:27 pm
On a quiz show, something about 1st., 2nd. 3rd. are cardinal numbers; 1, 2, 3 are ordinal numbers.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 28 December, 2023, 07:17:38 pm
Quote
In the first half of 2023, the average cost of an EV in China was US$33,000 (£26,040), more than half the US$70,700 (£55,800) people pay for EVs in Europe and the US$72,000 (£56,800) paid in the US.
It's more or less right.
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 19 January, 2024, 02:17:13 pm
Quote
The infant is the third to be found in Newham in four years, with a girl left in a park in February 2019, and a boy on the street in January 2020.

Methinks that’s five years…

https://www.bbc.co.uk/news/uk-england-london-68025769 (https://www.bbc.co.uk/news/uk-england-london-68025769)
Title: Re: Arithmetic that makes you cringe
Post by: mrcharly-YHT on 19 January, 2024, 03:14:08 pm
6÷2(1+2) = 9

Quote
Some historical justifications tell that the answer is 1, but today we interpret that differently.

FFS.

This is from a website purporting to teach mathematics.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 19 January, 2024, 03:55:04 pm
So which is correct, 9 or 1? I remember learning BEDMAS, but googled and found BODMAS, PEMDAS and GEMDAS; all pretty similar though. According to my vague memory it should be 9 but I can see how it could also be 1. I also found this:
Quote
I’m sorry to have to inform everybody, but there is not a universally recognized convention for evaluating this expression. The three come up with different results. There are three common conventions currently in practice:

PEMDAS/BODMAS:
This is a set of rules for order of expressions that is taught to a large number of students at the advance arithmetic and early algebra phases of their schooling. For the expression given in the question it directs:
6/2(1 + 2) = 6/2(3) —Do what is in the parentheses first.
= 6/2(3) — No change because next come handling exponents, of which there are none.
= 3(3) —Do multiplications and divisions in order from left to right.
= 9. —Repeating previous step since there is one division and one multiplication.
There are problems with this set of rules because they were designed for advanced arithmetic and early algebra. They do not handle more advanced expressions. For advanced arithmetic, typically all operations are expressed explicitly, so that 6/2(1 + 2) would not be given, but instead 6/2 × (1 + 2). We will see in the next convention how this distinction can be important, and standard PEMDAS/BODMAS do not distinguish the two expressions.
Traditional practice of professional mathematicians and physicists (which excludes pre-university mathematics and science teachers):
If we want to see how things are really done, let’s go to the professionals, rather than depending on overly simplified textbooks that cover only what you need to know now (which is what PEMDAS/BODMAS does). The basic rules are very similar to PEMDAS/BODMAS, with two exceptions: stacked exponentiation is regarded as to be done top-down (sometimes called right-associative), whereas PEMDAS/BODMAS usually does not specify a direction or, if they do, is left-to-right, which is backwards from professional practice; juxtaposed implicit multiplication has lower precedence than exponentiation (like PEMDAS/BODMAS) but higher precedence than all other multiplications and divisions (unlike PEMDAS/BODMAS). In other words, if you write 1/2a, the 2a is regarded as a tightly bound entity and to be treated as a single unit in the context of multiplications and divisions, so it means 1/(2a), not (1/2)a; PEMDAS/BODMAS would treat it as (1/2)a instead. It is necessary to distinguish juxtaposed multiplication from other expressions of multiplication to be able to handle properly formulas like:
sin 4u = 2 sin 2u cos 2u
as the first step in showing the expansion of sin 4u. Juxtaposed multiplications must be done before the trigonometric operators, which must be done before the non-juxtaposed multiplications. For the expression given in the question:
6/2(1 + 2) = 6/2(3) —Do what is in the parentheses first.
= 6/2(3) — No change because next come handling exponents, of which there are none.
= 6/6 —The juxtaposed multiplication 2(3) is to be done next.
= 1. —The only operation remaining.
Clarity reigns:
Because of the confusion that arises between methods 1 and 2, and confusion needs to be avoided, it has become in recent years standard practice among publishers of technical journals, the General Conference on Weights and Measures (responsible for defining the metric system), and several other standardization organizations to prohibit expressions that involve a division symbol followed on the right by a multiplication or another division within one term, unless explicit bracketing or use of vertical layout make it completely clear and explicit in which order the affected divisions and multiplications are to be done. For the expression given in the question, these rules regard 6/2(1 + 2) as undefined. We are not going to play some cutesy games like “I know PEMDAS/BODMAS and I’m going to see whether you do or I can trick you, so I am deliberately writing it hoping to confuse you.” For somebody who acts that way, you are being pretentious, acting like “I know more mathematics than you do and I am going to show you”, but in fact you are demonstrating that you know less mathematics, because you are showing that you do not realize that a key part of mathematics is to express your thoughts clearly and unambiguously without reliance on some convention not universally recognized. Therefore, the expression in the question cannot be validly evaluated unless it is rewritten in another form such as:
(6/2)(1 + 2) [9], 6/(2(1 + 2)) [1], 62(1+2)
 [9], 6(1+2)2
 [9], 62(1+2)
 [1]. [Brackets after each expression indicate the resulting value.]
“Rules of mathematics” are not some stagnant ideas thought up once, written down, and never changed again. As technology changes, the modes of conveying ideas change as well, and the different modes have different new abilities never available before in some cases and more restrictions in other cases. This sometimes requires that the rules change. The rules for how multiplications and divisions are handled have changed several times in the last 120 years. They are changing again. Convention 3 (to be explicit as to intent) is rapidly becoming the new dominant convention. In this regard, PEDMAS/BODMAS that is so treasured by some people will soon become outmoded—even dead—if it is not changed to accommodate this prohibition of multiplications and other divisions immediately following a division.
https://www.quora.com/What-is-the-answer-to-6-2-1+2

Which implies the answer is "be clearer in writing questions", but might equally be bullshit.
Title: Re: Arithmetic that makes you cringe
Post by: mrcharly-YHT on 19 January, 2024, 04:07:29 pm
The juxtaposition rule applies. Otherwise you can't do algebra.


8 / 2(2+2) is the same as 8 / 2(x), where x=(2+2)
I'm pretty sure you would agree that 8 / 2(x) = 8/2x, NOT 8/2 * x
This is the juxtaposition and necessary to be able to do algebra.
writing 8 / 2(2+2)
is not the same as
8 / 2 * (2+2)

the problem is that the original equation isn't 'valid syntax' for arithmetic.

If you wrote
8 / 2(x), where x=(2+2)
then it is obvious that it resolves to

8 / (2*4)
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 19 January, 2024, 04:36:01 pm
Ah. I don't remember that from O level. But then that was in the days of handwriting. And I might just have forgotten it. But then they clearly aren't taking any notice of it in the example. So it should be either 6/2 * (1+2) = 9 or 6 / 2(1+2) = 1.
Title: Re: Arithmetic that makes you cringe
Post by: mrcharly-YHT on 19 January, 2024, 04:47:56 pm
Ah. I don't remember that from O level. But then that was in the days of handwriting. And I might just have forgotten it. But then they clearly aren't taking any notice of it in the example. So it should be either 6/2 * (1+2) = 9 or 6 / 2(1+2) = 1.

6 / 2*(1+2) = 9
6 /( 2*(1+2)) = 1

When I did the equivalent of O levels, 8 / 2(2+2) would have been rejected. The use of a . to indicate multiplication was introduced with algebra, so

8 / 2.x where x = (2+2) would have been accepted.

The dot was quickly abandoned, as it really doesn't work well with people who have crappy handwriting.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 19 January, 2024, 04:55:27 pm
the problem is that the original equation isn't 'valid syntax' for arithmetic.

I'd go with that.  Normally (traditionally or whatever) a division would be written as

dividend
--------
devisor

meaning that anything below the line is effectively in brackets (ditto above the line).  Write everything in the same line and you have to insert the brackets, otherwise you've got arithmetic à la Facebook where the loudest Karen wins.

WRT BODMAS and such pontes asinorum, they're all inadequate because multiplication and division have equal priority, as do addition and subtraction. A better notation might be BE[M,D][A,S] where comma-separated items in brackets have equivalent priority, but it wouldn't trip as lightly off the tongues of infants.
Title: Re: Arithmetic that makes you cringe
Post by: mrcharly-YHT on 19 January, 2024, 04:57:05 pm
Agreed.

Do away with the dividing line and you have to use parentheses for clarity.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 20 January, 2024, 12:36:37 pm
Yup.

I'd write that as either:

  6
------
2(1+2)


or:

6
- × (1+2)
2


Or 6/(2(1+2)) or (6/2)*(1+2) inna computer.

'÷' is a primary school thing for carefully curated simple arithmetic questions (and less carefully curated quiz questions on newspaper websites and the like), and tends not to appear in real world mathematics.

In this context it's being used as a trap for teaching BODMAS, which is fair enough (it's what I was taught as a snotty 11 year old), but I also expect things to be right-associative, which I don't remember being explicitly taught - either because I've recycled the neurons (likely) or because I did enough SCIENCE to learn it by osmosis.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 20 January, 2024, 12:48:56 pm
The dot was quickly abandoned, as it really doesn't work well with people who have crappy handwriting.

I didn't come across the dot until scalar products.  Which might have been the first year of university, now I think about it.  Crappy handwriting was pretty much compulsory at that point.
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 20 January, 2024, 12:58:41 pm
As I recall, when converting to reverse Polish you have to parse expressions from right to left.  Long time since I mucked about with compilers' guts, though.
Title: Re: Arithmetic that makes you cringe
Post by: MattH on 21 January, 2024, 09:32:56 am
I wonder what percentage of people here instinctively came up with 1 or 9?
I thought 1, due to the lack of a * before the parenthesis. If the * was there, I'd have said 9.

When writing code, I tend to be very explicit and put in more () than are strictly needed in formulae, to make it clear what is going on and less likely to make an error later when I or someone else changes the code.

The original way the formula was presented is simply sloppy and seemingly designed specifically to trick people by being ambiguous.
Title: Re: Arithmetic that makes you cringe
Post by: rafletcher on 21 January, 2024, 10:10:38 am
As I recall, when converting to reverse Polish you have to parse expressions from right to left.  Long time since I mucked about with compilers' guts, though.

Indeed. The 2 results might be considered to be the the difference between HP calculators (RP notation, gives 1) and IBM Commodore calculators (9) that did the functions as you entered them. Sort of.

FWIW I instinctively got 1 as the answer. Parenthesis first, then multiply before divide.
Title: Re: Arithmetic that makes you cringe
Post by: mrcharly-YHT on 21 January, 2024, 10:37:48 am
I wonder what percentage of people here instinctively came up with 1 or 9?
I thought 1, due to the lack of a * before the parenthesis. If the * was there, I'd have said 9.

When writing code, I tend to be very explicit and put in more () than are strictly needed in formulae, to make it clear what is going on and less likely to make an error later when I or someone else changes the code.

The original way the formula was presented is simply sloppy and seemingly designed specifically to trick people by being ambiguous.
I thought '1', then saw the alternative calculation promoted by Neil Does Maths and the Art of Mathematics, so did some research.

Cross with both of them, because by saying '9', they will confuse the heck out of students when those students are introduced to algebra.

Really, they should have rejected the syntax and explained why.
Title: Re: Arithmetic that makes you cringe
Post by: HTFB on 21 January, 2024, 10:54:30 am
To throw in another example of how the choice of notation affects the conventional order. In arithmetic "and" and "plus" are the same operation, just pronounced differently. So one hundred plus five means the same as one hundred and five: but three times one hundred plus five is not the same as three times one hundred and five.
Title: Re: Arithmetic that makes you cringe
Post by: Kim on 21 January, 2024, 12:41:44 pm
Except when 'and' is a bitwise boolean operation.  100 and 5 is of course 4.
Title: Re: Arithmetic that makes you cringe
Post by: tom_e on 25 January, 2024, 01:41:39 pm
I'm gonna nominate this quite interesting article about Geothermal power in Kenya (https://www.theguardian.com/environment/2024/jan/25/our-contribution-to-a-cleaner-world-how-kenya-found-an-extraordinary-power-source-beneath-its-feet)

for what appears to be blind copying from an obviously-wrong bit of source material:

Quote
Geothermal energy had its start in the small settlement of Larderello, Italy in 1904. The small plant provided a mere 10kW of energy, just enough to power five lightbulbs.

The mind boggles slightly.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 25 January, 2024, 05:26:37 pm
Leaving aside the omission of 'h', Kenya must have very viscous darkness to need 2kW lamps.

BTW, "32ºF (1.6ºC)" - <-- there's a free minus sign for you.
Title: Re: Arithmetic that makes you cringe
Post by: hellymedic on 26 January, 2024, 05:17:35 pm
32F = 0C
-32 F = -35.5555C
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 26 January, 2024, 05:24:33 pm
Oops - it was 29ºC. Corrections beget errers.
Title: Re: Arithmetic that makes you cringe
Post by: Lightning Phil on 26 January, 2024, 10:32:33 pm
I wonder what percentage of people here instinctively came up with 1 or 9?
I thought 1, due to the lack of a * before the parenthesis. If the * was there, I'd have said 9.


* is a coding thing rather than how it would be written in maths notation. Just like you’d write 3y not 3*y when writing the equation out.
Title: Re: Arithmetic that makes you cringe
Post by: Cudzoziemiec on 27 January, 2024, 01:15:54 pm
I do wonder if this stuff should be in "Grammar that makes you cringe" not "Arithmetic..."
Title: Re: Arithmetic that makes you cringe
Post by: T42 on 27 January, 2024, 05:32:10 pm
I do wonder if this stuff should be in "Grammar that makes you cringe" not "Arithmetic..."

Maths notation being a formal grammar, yes.
Title: Re: Arithmetic that makes you cringe
Post by: Giraffe on 07 February, 2024, 08:24:29 am
 can't quite get this:
"UK halves emissions by 50%". The UK has halved its emission over the last 32 years - OK, but that headline... Could be 25% I suppose.