For the second time this week I have read an article suggesting a slide rule be run over a potential corporate purchase.
What do they think they mean?
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Just 'check the figures'? Don't know why they would prefer a slide rule over a calculator though...
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I think they mean do some serious (financial) calculations.
A slide-rule is a "mechanical analog computer", according to Wikipedia and predates pocket calculators by some margin (invented around 1620–1630, apparently). Thus it has passed into common parlance.
Last edited by: FocalPoint on Wed 16 May 12 at 15:11
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Do some calculations to check the financial viability of the purchase.
I doubt they will be looking for the old engineer in the back office that has just given up his log tables. :-)
Edit. I must learn to type faster. And I didn't need Wiki - just answering before Number Cruncher turns up and gives us all a refresher!
Last edited by: Crocks on Wed 16 May 12 at 15:14
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I've still got my slide rule from school days. I like to confuse and irritate my son by calculating his homework things on it faster than he can on his scientific calculator. He doesn't think it can possibly work as it doesn't have a screen or a keypad.
Last edited by: Humph D'Bout on Wed 16 May 12 at 15:24
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Don't remind be about Log's, i was quite good at them a lieftime ago, doubt i could work them again without some serious revision, preferred them to slide rules though.
Is it true that culculators are allowed in Maths exams now?
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>> Is it true that culculators are allowed in Maths exams now?
The Lad is doing part of his Maths AS today. One calculator paper and one without IIRC.
The calculator just removes some of the legwork, at that level it's the principles that count. Garbage in will beget garbage out!!
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Garbage in will beget garbage out!!
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works for me, hopeless with a calculator, still do most of my own calculations the old way.
I changed schools during a home move and ended up in a modern one signed up to the new method of Maths coming in mid 60's, i hadn't a clue and hated the place with a vengeance, luckily we moved again shortly after and somehow managed to get accepted at my last school, still mortars and capes and the old ways, much better there was back on home turf.
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Still have one of these somewhere and a set of pro-rata tables.
www.bobmockford.co.uk/calculating/reckoner/
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I still keep my micrometer and set of Vernier calipers safe from my reps days many years ago....
Happy days?, No, not really so why can't I throw them away?
Pat
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>> Still have one of these somewhere and a set of pro-rata tables.
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>> www.bobmockford.co.uk/calculating/reckoner/
I found some interesting pages in that website. tinyurl.com/8y2x2qf tinyurl.com/6mx3e45
Last edited by: L'escargot on Thu 17 May 12 at 10:23
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>> culculators
Next thing they'll allow dictionaries into English exams.
:>)
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>> >> culculators
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>> Next thing they'll allow dictionaries into English exams.
:-))))) drat, well spotted.
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>> Don't remind be about Log's, i was quite good at them a lieftime ago, doubt
>> i could work them again without some serious revision, preferred them to slide rules though.
A slide rule is just an instrument in which the marked length is proportional to the log of the number. I started collecting them a few years ago but it looks as if most people have just thrown theirs away. By the way, I've still got my log tables. In a few years they'll be collectible and worth a lot of money ~ I hope!
Last edited by: L'escargot on Wed 16 May 12 at 17:15
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>> Don't remind be about Log's, i was quite good at them a lieftime ago, doubt
>> i could work them again without some serious revision, .........
All you need to know is that for multiplication you add the logs of the numbers together before antilogging, and for division you subtract the log of the denominator from the log of the numerator before antillogging. This is the principle of a slide rule.
Last edited by: L'escargot on Thu 17 May 12 at 10:35
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>> All you need to know is that for multiplication you add the logs of the
>> numbers together before antilogging, and for division you subtract
Thanks L'es, i seemed to recall it was adding and subtracting, but seeing as its 41 or more years since i used log tables i was no longer sure.
I have a couple of my late brothers (electrical engineer following first electrical officer in the Merchant after RN) slide rules kicking about...in truth i have drawer fulls of his stuff and i simply cannot part with it through loyalty...i must dig one out and see if i can still use it.
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>>I like to confuse and irritate my son by calculating his homework things on it faster than he can on his scientific calculator.
In a previous life, I had to convert denary to hexadecimal and vice versa. New, young whippersnapper got himself a calculator to do the job. We'd always double check each others work and it would be neck and neck as to who'd get the result first (although I did use more paper).
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Well, to be honest here, I'm not always (or even often) faster than a calculator when using a slide rule but my son doesn't know how to read one so I get away with it by saying, "Well I've got an answer, what did you get?"...When he tells me I pretend to double check and confirm or otherwise...
These things are important in maintaing the status quo. I fear though, that ere long, I shall be rumbled.
:-)
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I swapped schools two years before my O levels, I landed in class that was doing "quadratic equations" I'd never heard of them !
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>> I landed in class that was doing "quadratic equations" I'd never heard of them !
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Happy days! Was the formula something like X= -b + or - the sq root of b sq over 2a ?
And I did that from memory...
Last edited by: Clk Sec on Wed 16 May 12 at 17:01
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.... and left out -4ac if I remember rightly.
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What are they for though ?
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I had no idea then, and have even less now.
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"What are they for though ?'
They are the answer to life the universe and everything
plus.maths.org/content/101-uses-quadratic-equation
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My winsome and talented (but scatty and non-academic) 10-year-old granddaughter came in several times the other evening to briefly borrow my calculator. About the fifth time I asked her what the calculation was and it was some simple bit of multiplication, 63X7 or something like that. Appalled, I told her sternly that stuff like that should be done in one's head in a few seconds. With a bit of prompting she did it fairly quickly, but I could tell she would revert to using the calculator even for that sort of thing unless discouraged. Seems to me that the young in this country are being deliberately moronized by their teachers, probably Chinese, Indian or Martian secret agents.
My youngest daughter, now over 30, had a talent in childhood for mental arithmetic, an entirely natural talent that led her to outpace the supermarket checkout when she was 6 or 7 years old. The maths teacher in her primary school crushed that talent utterly with a lot of balderdash about 'magic numbers' and the like. The stuff was so meaningless, roundabout and irrational that she had trouble understanding it. So did I, because actually there was nothing there to understand.
Stupid pompous young git he was, one of countless thousands entrusted by government with the task of demolishing the minds of the young.
Last edited by: Armel Coussine on Wed 16 May 12 at 17:32
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I was one of the first to permitted calculators in some exams. But it was early days, battery life was abysmal and I went into several exams with a spare battery, my slide rule and took the offered log tables.
Later, at university, calculators were pretty universal, but my trick for doing reciprocals in my head caused a bit of fun in lab work, owners of calculators didn't think a mere human brain could be quicker!
(Actually the trick is simple, learn reciprocals of all 1 to 10 digits, it's a linear scale so simple to interpolate and any owner of a slide rule will quickly learn as putting the decimal point in the right place is almost instinctive).
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>> In a previous life, I had to convert denary to hexadecimal and vice versa. New,
>> young whippersnapper got himself a calculator to do the job. We'd always double check each
In a previous life I had to convert Hexadecimal to Binary and viccy verccy, much easier than it sounds.
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In a previous life I counted in binary.
101010101010101010111 greetings to you all.
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The trouble these days is kids are taught maths at school, when what they need for real life is arithmetic.
I can get close to most percentages etc in the old noggin, but I was really please when the Chancellor made vat 20% - really simplified the calculation!
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I thought maths was arithmetic, plus a bit of algebra and geometry and so on. It's all so long ago and I've forgotten most of it although I did additional maths at O level.
Seems to me that the problem is this ludicrous faffing idiot wish to make maths 'interesting' by breaking it down into random disconnected bits. Actually if you make (and I mean make) children learn multiplication tables up to 12X when they are quite small, then move on to other operations including simple fractions and so on followed by the decimal system, it all hangs together logically and nippers know that 20 per cent means a fifth. How many ten-year-olds just know that these days, so they can do their dads' VAT calculations in their heads saving an accountant's undeserved slice?
Last edited by: Armel Coussine on Wed 16 May 12 at 22:53
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I see the effects of this misguided attempt to make maths interesting all too frequently.
The lack of basic maths skills in the students I teach at the polyversity means that the material I use has to be dumbed down from the level it should be taught at. If I taught the remedial maths, I would have no time left to teach the engineering!
I don't really think it's meaningful or helpful to anyone to turn out engineers into the job market who can't really design components competently or safely beyond making them look right and well rendered on a CAD system, and is one reason [of a few!] why the polyversity isn't a long term part of my career plan.
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It's no use blaming the calculators. Give anyone a tool which will make a job easier (inasmuch as it requires less mental effort) and they'll use it; witness reversing sensors/cameras as a classic case in point. The fun begins when you have to manage without them; anyone who's seen the hopeless expression on the face of someone under 40 confronted with a simple piece of mental arithmetic will know what I mean.
Like Slidingpillar, calculators were in their infancy when I did school exams, and IIRC they weren't permitted in the exam itself. Not that they'd have done me any good for I was never much cop at maths; I learned far more from my mother, having inherited (or more likely learned) her ability to add up the week's shopping as I went along. Still stands me in good stead today as many supermarkets have found to their cost.
Totally agree with AC; the teaching of mathematics, along with many other subjects, suffered dreadfully once teachers were allowed to be "trendy" and we are now reaping the whirlwind of that policy.
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Re the OP, in my market research days there was a lot of percentaging and so on, with Swedish and American mechanical calculators bouncing about on the desks and sometimes slide rules having to be used.
I liked especially the cylindrical job, a heavy serious machine with a damped action which, because of its spiral scale, was the equivalent of a normal slide rule several feet long... ooh yeah, super accurate that one, three or four decimal places for what it was worth...
:o}
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A boy at school had one of those - it looked a bit like Nelson's telescope, and as you say, was the equivalent of a straight rule many feet long.
There was another boy who could add up figures as fast as someone read them out.
At the end of term the form master checked his addition of everyone's marks by reading them out, and then we all wrote them down and added them up.
But as he read out 97, 48, 34, 85, 78 etc ...as soon as he had finished reading, the boy just piped up 793. He was always right, so no one bothered any more.
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>>>> There was another boy who could add up figures as fast as someone read them
>> out.
>>
Where is he now?
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A friend used to work as a part time barman in a very busy Edinburgh pub at weekends to supplement his income. He appeared to be able to add up multiple drinks orders as fast as that.
When one of us mentioned how impressive that was he admitted that it was all about getting close enough and saying it confidently !
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>> A friend used to work as a part time barman in a very busy Edinburgh
>> pub at weekends to supplement his income. He appeared to be able to add up
>> multiple drinks orders as fast as that.
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>> When one of us mentioned how impressive that was he admitted that it was all
>> about getting close enough and saying it confidently !
Yeah they still do it now, every drink is 3 quid then add 85p to final bill.
6 drinks = 18 quid, add 85p total bill 18.85
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>> Yeah they still do it now, every drink is 3 quid then add 85p to
>> final bill.
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>> 6 drinks = 18 quid, add 85p total bill 18.85
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Problem is that nowadays they serve you the drinks, ask you if that's all, walk to the till, swipe their card, key in the prices, walk back to you and tell you the price; you give them a £20 note, they then walk back to the till, wait for someone else to finish working in that space, swipe their card again, wait for the screen to tell them how much change they need to give you (that's the bit that infuriates me!) and then walk back with it and sullenly tell you to have a nice day. Five minutes of which has just been wasted.
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"Yeah they still do it now, every drink is 3 quid then add 85p to final bill."
Last time I worked in a bar it was 2/6 per drink plus 5d but glad to see the principle hasn't changed
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>> "Yeah they still do it now, every drink is 3 quid then add 85p to
>> final bill."
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>> Last time I worked in a bar it was 2/6 per drink plus 5d but
>> glad to see the principle hasn't changed
Blimey at those prices it must have been at Mr Hogarths Gin and Porter shop, the one between Newgate Jail, and Sweeny Todds pie shoppe
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No, the Princess Alice in Forest Gate about 1968/1969
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>> Where is he now?
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Dot.com millionaire, leading light in IT and telecommunications, chairman of umpteen companies, on board of various international charitable bodies, freeman of the city of London.
Still adding up.
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>> It's no use blaming the calculators. Give anyone a tool which will make a job
>> easier (inasmuch as it requires less mental effort) and they'll use it; .......
I gave "er indoors (who left school and started work the day afterwards on her 14th birthday) one of my old calculators, but she doesn't use it and she still resorts (satisfactorily) to mental arithmetic.
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>> In a previous life I had to convert Hexadecimal to Binary and viccy verccy, much
Same here. A printer controller we were working with at the time had its configuration settings in groups of 16 bits, with each 16 bit group displayed as four hex digits.
To make a configuration change, you had to find the hex group that contained the relevant bit (or bits), convert the hex to binary, find the bit (or bits) you wanted to change, make the change in binary, then convert the binary back to hex.
I could do this with a pen and paper, but never in my head.
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Just so long as nobody runs over my slide rule .........!
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I just don't see how you can run a slide rule over something.
You can (metaphorically) run a ruler/tape measure over it. With those numbers you can then use your slide rule to evaluate the worth.
I think people think a slide rule is a sophisticated sort of ruler.
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Whilst a slide rule works on the same basis as logs, it must be remembered that it is only generally accurate to a low number of significant figures.
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>> Whilst a slide rule works on the same basis as logs, it must be remembered
>> that it is only generally accurate to a low number of significant figures.
>>
Most people who use a calculator then go and round up (or down) the final result.
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There was a young barmaid from Sale
On her breasts were the prices of ale
And on her behind for the sake of the blind
Was the same information in braille
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Running a slide rule over it... - Focusless
