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Is there any point to the 12 times table?

blog.wolfram.com

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Re: Is there any point to the 12 times table?

#181

Post by antod »

Widdershin wrote: post #158
antod wrote: post #116

Earlier quoted context omitted.

Same in New Zealand. The only times I ever saw anything with 12x tables it had escaped from the US education market and had exercises involving nickels, dimes and quarters etc.

My experience in New Zealand differs, we learned the 12x tables at primary school and there was nothing vaguely imperial about it. This was around about a decade ago.

Interesting - my experience was in the early 80s.

I suspect getting the 12x table added to the NZ maths curriculum was probably the main deliverable of the 2001 Knowledge Wave Conference.

Re: Is there any point to the 12 times table?

#182

Post by yitchelle »

golergka wrote: post #128
Animats wrote: post #21

Only in non-metric countries. Back in the British era of pounds, shillings, and pence, hardware had to be built to do arithmetic in that system. This resulted in one of the strangest, and most complex, purely mechanical computing devices ever built - the McClure Multiplying Punch [1], from Powers-Samas. This device came out in 1938. The comparable IBM machine was the IBM 602 Multiplying Punch, but IBM only did decima…

Just imagine how strange today's world will look when people will switch to binary (and probably hex for writing).

Haven't you heard, we have a new invention call computer, or something like that, to help us out here. :-)

Re: Is there any point to the 12 times table?

#183

Post by aaron695 »

mserdarsanli wrote: post #147
gknoy wrote: post #142

Earlier quoted context omitted.

I don't know that it's meant to shill the product -- rather, that's the tool that he has handy. I work all the time with Python, and frequently open an IPython shell to do some quick math ("what's the average of 4d6 pick 3?" "what is X% of my paycheck?" "how much do I need to contribute to max out my $FOO?"), simply because it's easier than a calculator. I mean, sure, it's advertising Mathmatica, but it doesn't seem…

I don't work with Python, but when I want to multiply some numbers, I type `python` into terminal and use it as a calculator, as it allows me to do such operations quickly. It sounds weird that someone opens an IDE and waits ten seconds looking at a splash screen to do a simple multiplication.

Dogfooding

Re: Is there any point to the 12 times table?

#184

Post by Wildgoose »

Scarblac wrote: post #103
clarkmoody wrote: post #79

This type of post is perfect Hacker News material! 1) Challenge an existing assumption about something we all do 2) Hand-wave some first-order guesses as to why we do it 3) Get nerdy with code and graphs and come to your conclusion, along with helpful suggestions for bettering the reader With no prospect of the pre-decimal money system returning, I can only conclude that the logic behind this new priority is simply,…

But do we all learn tables up to 12? In the Netherlands it's only up to 10 for as far back as I know.

I learned all the way up to the 12 times tables here in England, I was born in 1965. My kids only seem to have learned up to their ten times table however.

Personally I strongly believe that this is so important that it should be enforced by rote memorisation very early on (as in my case).

For some reason far too many people see no problem with insisting children learn their alphabet to ensure literacy but suddenly lose interest when it is times tables in order to ensure numeracy.

Fortunately we have just had a (wrongly much derided) Education Secretary in Government called Michael Gove who has done an excellent job at demanding that these basics are covered and as a result is now widely (and wrongly) hated.

He has also insisted that school IT courses should involve teaching programming. Up to now, they have just been about to create a Microsoft Powerpoint presentation, or how to use Microsoft Word. Yes, seriously. That bad. They squandered the early lead the UK had with IT by dumbing down everything to such an extent that no bright kid would want anything to do with computers.

Re: Is there any point to the 12 times table?

#185

Post by Wildgoose »

switch007 wrote: post #89

It's moved from "should" to must. "Every child in England will be expected to know their times tables before leaving primary school from next year. Pupils will be tested against the clock on their tables up to 12x12 in new computer-based exams that the Department of Education (DfE) said were part of the government’s “war on innumeracy and illiteracy”." http://www.theguardian.com/education/2016/jan/03/pupils-face... G…

Gove did a fantastic job as Education Secretary and that is why he is now hated by a teaching profession being forced to do their job.

I am not and never have been a Tory, but he is the one Tory minister I can respect. (The rest are dreadful).

Re: Is there any point to the 12 times table?

#186

Post by kuschku »

btilly wrote: post #154
kuschku wrote: post #149

Earlier quoted context omitted.

In math, we prefer to use either (101010)_2 or (101010)2 or 101010_2 – which represents (42)_10 (With TeX formatting implied)

We do? In my experience mathematicians almost always assume base 10 and don't bother indicating it. In fact we mostly indicate the base when there is a good possibility that it isn't 10, and any stray numbers fail to have a base represented, they should be assumed to be base 10. (Mathematical notation mostly uses sensible defaults except for differential geometry.)

Yes – but if we do want to talk about other bases, we use this format. Implicit default for a number x is obviously (x)_10, as mathematicians are lazy.

Re: Is there any point to the 12 times table?

#187

Post by panglott »

pklausler wrote: post #141
yes_or_gnome wrote: post #47

Earlier quoted context omitted.

I am in the process of reading 'The Story of French' by Nadeau and Barlow. There's a chapter on how France was able to push their influence, during the renaissance, to get the world to switch to the metric system. Prior to developing the metric system, France had no standard for the pound; unlike England. This was the height of enlightenment in France, so the reformers wanted to replace the Gregorian Calendar with a…

Vernor Vinge's novel, "A Deepness in the Sky", involves an spacefaring civilization that uses metric time (Ksec, Msec) after discarding Earth-based units. A feature of the book: the author never gives a footnote explaining how to convert these units to familiar ones, so you have to work it out yourself. Which means that you'll never forget it once you've done the homework. (Also, there's the old rule-of-thumb from Gr…

The problem with kiloseconds/megaseconds/&c. is that the time units are simply not human scale. Your base units are 1 second, 16 minutes, 11 days, and 31 years. If you want to talk about a period of a few days, you're talking about hundreds of 16-minute periods. If you're talking about a few years, you're talking about hundreds of near-fortnights. If you sleep one unit of time per two waking units, you'll have a couple of leftover time units here and there. http://panglott.blogspot.com/2009/06/kiloseconds-brevels.htm... http://panglott.blogspot.com/2013/06/timekeeping-in-embassyt...

Re: Is there any point to the 12 times table?

#188

Post by JoeAltmaier »

panglott wrote: post #187
pklausler wrote: post #141

Earlier quoted context omitted.

Vernor Vinge's novel, "A Deepness in the Sky", involves an spacefaring civilization that uses metric time (Ksec, Msec) after discarding Earth-based units. A feature of the book: the author never gives a footnote explaining how to convert these units to familiar ones, so you have to work it out yourself. Which means that you'll never forget it once you've done the homework. (Also, there's the old rule-of-thumb from Gr…

The problem with kiloseconds/megaseconds/&c. is that the time units are simply not human scale. Your base units are 1 second, 16 minutes, 11 days, and 31 years. If you want to talk about a period of a few days, you're talking about hundreds of 16-minute periods. If you're talking about a few years, you're talking about hundreds of near-fortnights. If you sleep one unit of time per two waking units, you'll have a coup…

Just make 100,000 seconds in a 'day' and be done with it.

Re: Is there any point to the 12 times table?

#189

Post by Retric »

zeveb wrote: post #69
Retric wrote: post #15

Earlier quoted context omitted.

The first 3 prime numbers are 2, 3, 5. Base 10 and base 12 both use two of them. (12/4=3 yay, but 10/4 = 2.5 so meh) The same is true of base 6 or base 15. Every other prime number repeats so switching is pointless, unless you divide by 3 vastly more often than by 5. PS: Several ancient systems use base 60 which uses 2, 3, and 5 and may have been created by joining a base 6 system with a base 10 system. However, base…

> Every other prime number repeats so switching is pointless, unless you divide by 3 vastly more often than by 5. It's highly probable that in duodecimal one would divide by 2, 3, 4, 6, 8 & 9 as often as one divides by 5 in decimal, and avoid 5 as much as one avoids 3 & 7 in decimal.

You can divide by 2, 4 or 8 just fine in base 10.

3 and 9 are also fast though you get either a remainder or a repeating number. So, really the advantage is 6 vs 5.

Re: Is there any point to the 12 times table?

#190

Post by SixSigma »

trgn wrote: post #53
SixSigma wrote: post #3

I recently worked with a person who had to do her three times table using her hands, starting from 3. She would still struggle at about 6 or 7 times. We worked behind the counter in a builder's merchant. She is no longer working for us.

Due to some airline delays, I was trying to schedule a new flight. I ended up showing a boarding pass to an attendant at the booth and asking something along the lines of "I'd like to make this connection". The ticket said departure "22.17". She asked me "What's that in `real` time?". Two more from the garden center: I was looking for a pump for an ornamental pond, and the pumps were advertised by the amount of gallo…

Even crazier, because no doubt you specify the scoop size when you buy it. Ours are 2 or 3 cubic meters. They also have weight readings in the cab for the very scenario you are describing.
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