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By (user no longer on site) OP   
over a year ago

do we only learn our times tables up to 12 x ??

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By *isscheekychopsWoman
over a year ago

The land of grey peas and bacon

1x2 is 2

2x2 is 4

3x2 is 6

4x2 is 8

5x2 is 10

6x2 is 12

7x2 is 14

8x2 is16

9x2 is 18

10x2 is 20

11x 2 is 22

12x 2 is 24

I'm a clever girl

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By (user no longer on site) OP   
over a year ago


"1x2 is 2

2x2 is 4

3x2 is 6

4x2 is 8

5x2 is 10

6x2 is 12

7x2 is 14

8x2 is16

9x2 is 18

10x2 is 20

11x 2 is 22

12x 2 is 24

I'm a clever girl "

Gold star

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By (user no longer on site)
over a year ago


"do we only learn our times tables up to 12 x ?? "

Just a guess - but is it related to old imperial measures and pre decimal currency?

Both of which I'm too young to know anything about!

Any 'oldies' know the answer?

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By (user no longer on site)
over a year ago


"1x2 is 2

2x2 is 4

3x2 is 6

4x2 is 8

5x2 is 10

6x2 is 12

7x2 is 14

8x2 is16

9x2 is 18

10x2 is 20

11x 2 is 22

12x 2 is 24

I'm a clever girl "

Copy and paste!

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By *ollie_JCouple
over a year ago

London

As said pre decimal currency but time, degrees of a circle and measurement (inches to a foot) could also be used.

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By (user no longer on site) OP   
over a year ago

I thought maybe because we counted items in dozens but then why did we do that? We have twelve months of the year so maybe something to do with that?

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By (user no longer on site)
over a year ago

In some schools now they are only teaching up to 10

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By *rightonsteveMan
over a year ago

Brighton - even Hove!


"I thought maybe because we counted items in dozens but then why did we do that? We have twelve months of the year so maybe something to do with that? "

Yes, it to do with eggs in dozens and bakers dozens (although that's 13) and imperial stuff.

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By *rightonsteveMan
over a year ago

Brighton - even Hove!

There used to be 12 pence in a shilling.

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By *rightonsteveMan
over a year ago

Brighton - even Hove!


"There used to be 12 pence in a shilling."

Hence the need to be able to do mental arithmetic in 12's.

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By (user no longer on site) OP   
over a year ago

But why were there 12 thingys in a whatsit? Who decided we needed 12 of them?

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By (user no longer on site) OP   
over a year ago


"In some schools now they are only teaching up to 10

"

I think in China they go up to 20

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By *icecouple561Couple
Forum Mod
over a year ago

East Sussex


"But why were there 12 thingys in a whatsit? Who decided we needed 12 of them? "

God. That is all.

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By *ollie_JCouple
over a year ago

London

I am guessing 12 apostles, 12 months.. 12 is a very Christian number that mixes astrology, religion, mathematics (360=12 x 30 degrees)

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By (user no longer on site)
over a year ago


"do we only learn our times tables up to 12 x ?? "

Because when you reach puberty and have a fit young female Maths teacher you tend to ignore the first 100 of 13x13 and lose focus for the rest of the lesson.

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By (user no longer on site)
over a year ago

Mainly because 12 contains all of 1,2,3,4 and 6 as factors. After that it's easy.

Have you tried chunking with 13?

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By *icecouple561Couple
Forum Mod
over a year ago

East Sussex

We learned up to twelve as people have correctly surmised because the imperial system of measurement was based on twelve inches in a foot and there were twelve Pennies in a shilling. I don't know why when the rest of the world or most of it uses decimal systems and don't even get me started on fractions.

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By *ollie_JCouple
over a year ago

London

After reading some google threads it seems that in Europe they only teach up to 10. Perhaps somebody from abroad can comment

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By *icecouple561Couple
Forum Mod
over a year ago

East Sussex


"After reading some google threads it seems that in Europe they only teach up to 10. Perhaps somebody from abroad can comment"

They only need to teach up to ten really, after that you can use what you know to work out the rest.

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By (user no longer on site)
over a year ago

Quick tip for yer 9 times table. Try it works, upto 10 for obvious reasons.

Place both yer hands out flat before you.

Choose the number you want to multiply by 9, say 3, count from the left and fold under that finger/thumb.

Now count the digits to the left of that : 2

Count the digits to the right : 7

3 x 9 is 27

Course, the quicker way is just to learn yer times table.

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By (user no longer on site)
over a year ago

If you stop at 10x10, you miss one of the interesting patterns.

11x11=121

111x111=12321

Learnt before calculators were common.

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By *rightonsteveMan
over a year ago

Brighton - even Hove!

Canis is correct in thinking it's 12's cos they are easy to divide and multiply. It's not from Romans as they tended to have coins in fours, so no idea really.

Ps. I can be talked to/referred to with no repercussions.

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By (user no longer on site) OP   
over a year ago


"

Quick tip for yer 9 times table. Try it works, upto 10 for obvious reasons.

Place both yer hands out flat before you.

Choose the number you want to multiply by 9, say 3, count from the left and fold under that finger/thumb.

Now count the digits to the left of that : 2

Count the digits to the right : 7

3 x 9 is 27

Course, the quicker way is just to learn yer times table. "

that's too complicated for me. I just think of the number below the number being timesed by 9 and then see what you add to it to make 9. Works up to 9x9

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By (user no longer on site) OP   
over a year ago

Google is no help with this let's think logically here. Who invented counting?? Traders? Farmers? The Chinese?

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By *ollie_JCouple
over a year ago

London


"Google is no help with this let's think logically here. Who invented counting?? Traders? Farmers? The Chinese? "

Most of the stuff has been mentioned already

But google duodecimal and look at origins of 12

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By *ollie_JCouple
over a year ago

London

I like the hand bone counting theory

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By *uke olovingmanMan
over a year ago

Gravesend

it was to do with the money .. twelve old pennies in a shilling .. twenty shillings in a pound .. twelve also is a better base for calculations than ten . you can divide twelve by 2,3,4, giving halves, thirds and quarters .. ten only divides by .2 and 5 giving halvrs and fifths .. numbers larger than twelve can be calculated from the numbers up to twelve

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By (user no longer on site)
over a year ago

Is it bad that despite learning my timestables as a child, I've forgotten them all

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By (user no longer on site) OP   
over a year ago


"I like the hand bone counting theory "

the bones in fingers? That is feasible

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By (user no longer on site) OP   
over a year ago


"Is it bad that despite learning my timestables as a child, I've forgotten them all "

What prompted my post was me helping my granddaughter with her tables and thinking why stop at 12,why not go up to 15 or 20? I got my 12x table wrong lol

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By (user no longer on site) OP   
over a year ago


"it was to do with the money .. twelve old pennies in a shilling .. twenty shillings in a pound .. twelve also is a better base for calculations than ten . you can divide twelve by 2,3,4, giving halves, thirds and quarters .. ten only divides by .2 and 5 giving halvrs and fifths .. numbers larger than twelve can be calculated from the numbers up to twelve "

I'm wondering if we used base 12 before we used money though

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By *egasus NobMan
over a year ago

Merton

my brother is a math genius he will know the answer

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By *icecouple561Couple
Forum Mod
over a year ago

East Sussex


" Canis is correct in thinking it's 12's cos they are easy to divide and multiply. It's not from Romans as they tended to have coins in fours, so no idea really.

Ps. I can be talked to/referred to with no repercussions. "

do you mean me? I thought more than one person put the imperial measurements/ 12d in a shilling theory so mentioned no names to save leaving someone out.

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By (user no longer on site) OP   
over a year ago


"my brother is a math genius he will know the answer"

please ask him and let me know if he knows

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By (user no longer on site)
over a year ago

There was a time - several decades ago now - when the reason for learning the 12 times table was obvious. As a country using imperial measurements, we were all measuring in feet and inches and paying in shillings and pence, so multiplying by 12 was a common, everyday experience.

But for today's children this is all ancient history. Yes, we do still count eggs in dozens, and a lot of people - including most Americans - do still work in inches, but that's hardly justification for spending hours swotting those extra tables.

And yet, there's still a case for learning your "twelves", but the reason is to do with discovering patterns and building a confidence in handling numbers.

Once children begin to get comfortable multiplying numbers larger than 10, they start to get a feel for big multiplications. Knowing your 11 and 12 times tables can introduce intriguing patterns that might be missed if you stop at 10.

Much of the 11 times table is trivial to learn: 2 times 11 is 22, 8 times 11 is 88. And even when you get beyond 12, there are nice patterns to discover.

Want to multiply 11 by 23? Just take the two digits 2 and 3, add them together (makes 5) and put that number in the middle - 253. What about 36 x 11? Again, split the 3 and the 6 and put their sum (9) in the middle - 396. Lovely - though take care, if the two digits add to more than 9, this nifty trick doesn't work so neatly. 58 x 11... well 5+8 = 13, but the answer isn't 5138, that "1" actually represents a 100, and needs to be added to the 5 to give the answer 638.

There's a pattern that begins with 11 x 11, too. Multiply those two numbers together and you get 121. How about 111 x 111? The answer is 12321. Care to guess what 1111 x 1111 is? Yes, 1234321.

Meanwhile multiplying by 12 becomes much simpler when you realise it's the same as multiplying a number by 10 and then adding on double the start number. So 12 x 12 is 10 x 12 (=120) and then add 2 x 12 (=24) to give 120+24 = 144. This rule doesn't stop at your tables - 12 x 61 is the same as 10 x 61 (=610) plus 2 x 61 (=122) and if you can add 610 + 122 in your head you have the right answer, 732.

Do you need to memorise the answer to 12 x 12? Well, not really. As long as you know the strategy for working it out, you can get there almost as quickly by recalculating it in your head. But, of course, if you do a calculation often enough, it will become embedded in your memory, which will speed things up on those occasions when you need the answer.

Why stop at 12? You can continue to 13, 14… all the way up to 20 times table, as I believe happens in some countries. But hang on, if you understand your basic times tables up to 10, then you have the essential tools you need for working out, say, 19 x 14. And if you spend too much time rote learning the answers to these questions then you're going to miss out on time spent understanding how numbers work.

And it's understanding patterns and solving problems that maths is really all about.

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By *eMontresMan
over a year ago

Halesowen

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By (user no longer on site) OP   
over a year ago


"There was a time - several decades ago now - when the reason for learning the 12 times table was obvious. As a country using imperial measurements, we were all measuring in feet and inches and paying in shillings and pence, so multiplying by 12 was a common, everyday experience.

But for today's children this is all ancient history. Yes, we do still count eggs in dozens, and a lot of people - including most Americans - do still work in inches, but that's hardly justification for spending hours swotting those extra tables.

And yet, there's still a case for learning your "twelves", but the reason is to do with discovering patterns and building a confidence in handling numbers.

Once children begin to get comfortable multiplying numbers larger than 10, they start to get a feel for big multiplications. Knowing your 11 and 12 times tables can introduce intriguing patterns that might be missed if you stop at 10.

Much of the 11 times table is trivial to learn: 2 times 11 is 22, 8 times 11 is 88. And even when you get beyond 12, there are nice patterns to discover.

Want to multiply 11 by 23? Just take the two digits 2 and 3, add them together (makes 5) and put that number in the middle - 253. What about 36 x 11? Again, split the 3 and the 6 and put their sum (9) in the middle - 396. Lovely - though take care, if the two digits add to more than 9, this nifty trick doesn't work so neatly. 58 x 11... well 5+8 = 13, but the answer isn't 5138, that "1" actually represents a 100, and needs to be added to the 5 to give the answer 638.

There's a pattern that begins with 11 x 11, too. Multiply those two numbers together and you get 121. How about 111 x 111? The answer is 12321. Care to guess what 1111 x 1111 is? Yes, 1234321.

Meanwhile multiplying by 12 becomes much simpler when you realise it's the same as multiplying a number by 10 and then adding on double the start number. So 12 x 12 is 10 x 12 (=120) and then add 2 x 12 (=24) to give 120+24 = 144. This rule doesn't stop at your tables - 12 x 61 is the same as 10 x 61 (=610) plus 2 x 61 (=122) and if you can add 610 + 122 in your head you have the right answer, 732.

Do you need to memorise the answer to 12 x 12? Well, not really. As long as you know the strategy for working it out, you can get there almost as quickly by recalculating it in your head. But, of course, if you do a calculation often enough, it will become embedded in your memory, which will speed things up on those occasions when you need the answer.

Why stop at 12? You can continue to 13, 14… all the way up to 20 times table, as I believe happens in some countries. But hang on, if you understand your basic times tables up to 10, then you have the essential tools you need for working out, say, 19 x 14. And if you spend too much time rote learning the answers to these questions then you're going to miss out on time spent understanding how numbers work.

And it's understanding patterns and solving problems that maths is really all about.

"

very interesting

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By (user no longer on site)
over a year ago

Bravo

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By *ranny-CrumpetWoman
over a year ago

The Town by The Cross


"

Quick tip for yer 9 times table. Try it works, upto 10 for obvious reasons.

Place both yer hands out flat before you.

Choose the number you want to multiply by 9, say 3, count from the left and fold under that finger/thumb.

Now count the digits to the left of that : 2

Count the digits to the right : 7

3 x 9 is 27

Course, the quicker way is just to learn yer times table.

that's too complicated for me. I just think of the number below the number being timesed by 9 and then see what you add to it to make 9. Works up to 9x9 "

Works for infinity

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By *ranny-CrumpetWoman
over a year ago

The Town by The Cross

I think learning up to 12 x 12 is gross.....

Boom Boom !

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By (user no longer on site)
over a year ago

Yeah...what she said!

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By (user no longer on site)
over a year ago


"I think learning up to 12 x 12 is gross.....

Boom Boom !"

Granny, wise beyond her years

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By *r Mahogany70Man
over a year ago

Leicester


"There was a time - several decades ago now - when the reason for learning the 12 times table was obvious. As a country using imperial measurements, we were all measuring in feet and inches and paying in shillings and pence, so multiplying by 12 was a common, everyday experience.

But for today's children this is all ancient history. Yes, we do still count eggs in dozens, and a lot of people - including most Americans - do still work in inches, but that's hardly justification for spending hours swotting those extra tables.

And yet, there's still a case for learning your "twelves", but the reason is to do with discovering patterns and building a confidence in handling numbers.

Once children begin to get comfortable multiplying numbers larger than 10, they start to get a feel for big multiplications. Knowing your 11 and 12 times tables can introduce intriguing patterns that might be missed if you stop at 10.

Much of the 11 times table is trivial to learn: 2 times 11 is 22, 8 times 11 is 88. And even when you get beyond 12, there are nice patterns to discover.

Want to multiply 11 by 23? Just take the two digits 2 and 3, add them together (makes 5) and put that number in the middle - 253. What about 36 x 11? Again, split the 3 and the 6 and put their sum (9) in the middle - 396. Lovely - though take care, if the two digits add to more than 9, this nifty trick doesn't work so neatly. 58 x 11... well 5+8 = 13, but the answer isn't 5138, that "1" actually represents a 100, and needs to be added to the 5 to give the answer 638.

There's a pattern that begins with 11 x 11, too. Multiply those two numbers together and you get 121. How about 111 x 111? The answer is 12321. Care to guess what 1111 x 1111 is? Yes, 1234321.

Meanwhile multiplying by 12 becomes much simpler when you realise it's the same as multiplying a number by 10 and then adding on double the start number. So 12 x 12 is 10 x 12 (=120) and then add 2 x 12 (=24) to give 120+24 = 144. This rule doesn't stop at your tables - 12 x 61 is the same as 10 x 61 (=610) plus 2 x 61 (=122) and if you can add 610 + 122 in your head you have the right answer, 732.

Do you need to memorise the answer to 12 x 12? Well, not really. As long as you know the strategy for working it out, you can get there almost as quickly by recalculating it in your head. But, of course, if you do a calculation often enough, it will become embedded in your memory, which will speed things up on those occasions when you need the answer.

Why stop at 12? You can continue to 13, 14… all the way up to 20 times table, as I believe happens in some countries. But hang on, if you understand your basic times tables up to 10, then you have the essential tools you need for working out, say, 19 x 14. And if you spend too much time rote learning the answers to these questions then you're going to miss out on time spent understanding how numbers work.

And it's understanding patterns and solving problems that maths is really all about.

"

Take a bow, young lady

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By (user no longer on site) OP   
over a year ago


"I think learning up to 12 x 12 is gross.....

Boom Boom !"

lol made me laugh out loud that did

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By (user no longer on site)
over a year ago


"

Quick tip for yer 9 times table. Try it works, upto 10 for obvious reasons.

Place both yer hands out flat before you.

Choose the number you want to multiply by 9, say 3, count from the left and fold under that finger/thumb.

Now count the digits to the left of that : 2

Count the digits to the right : 7

3 x 9 is 27

Course, the quicker way is just to learn yer times table.

that's too complicated for me. I just think of the number below the number being timesed by 9 and then see what you add to it to make 9. Works up to 9x9

Works for infinity"

9x1 = 9

9x2 = 18 1+8=9

9x3 = 27 2+7=9

ad nauseam,

even 9x17=153 1+5+3=9.......spooky.

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By (user no longer on site)
over a year ago

Ultimately, all arithmetic simplifies to adding up the base numbers 0 to 9. All others are combinations of these.

From above, the hardest part of 2x61 is adding up two sixes= 12 insert the 0 = 120 then add two mores ones=122

Difficulty with subtraction? Add up to the number instead. Subtraction is merely finding the difference.

Example : 9673 less 3429

add 6 to the 3

add 2 to the 4

add 44 to the 29 ( 'cos 9 is larger than 3)

so, 6244 required

Practice these and it becomes easy. You will have plenty of time to double check the answer too.

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By *ollie_JCouple
over a year ago

London

[Removed by poster at 22/10/13 00:05:30]

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By (user no longer on site) OP   
over a year ago


"

Quick tip for yer 9 times table. Try it works, upto 10 for obvious reasons.

Place both yer hands out flat before you.

Choose the number you want to multiply by 9, say 3, count from the left and fold under that finger/thumb.

Now count the digits to the left of that : 2

Count the digits to the right : 7

3 x 9 is 27

Course, the quicker way is just to learn yer times table.

that's too complicated for me. I just think of the number below the number being timesed by 9 and then see what you add to it to make 9. Works up to 9x9

Works for infinity

9x1 = 9

9x2 = 18 1+8=9

9x3 = 27 2+7=9

ad nauseam,

even 9x17=153 1+5+3=9.......spooky."

but you have to work out 9x17 first, can't do it using my easy method of going one lower and adding up to make 9

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By (user no longer on site)
over a year ago


"

If you stop at 10x10, you miss one of the interesting patterns.

11x11=121

111x111=12321

Learnt before calculators were common. "

58008

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By (user no longer on site) OP   
over a year ago


"

If you stop at 10x10, you miss one of the interesting patterns.

11x11=121

111x111=12321

Learnt before calculators were common.

58008 "

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By (user no longer on site)
over a year ago


"

Quick tip for yer 9 times table. Try it works, upto 10 for obvious reasons.

Place both yer hands out flat before you.

Choose the number you want to multiply by 9, say 3, count from the left and fold under that finger/thumb.

Now count the digits to the left of that : 2

Count the digits to the right : 7

3 x 9 is 27

Course, the quicker way is just to learn yer times table.

that's too complicated for me. I just think of the number below the number being timesed by 9 and then see what you add to it to make 9. Works up to 9x9

Works for infinity

9x1 = 9

9x2 = 18 1+8=9

9x3 = 27 2+7=9

ad nauseam,

even 9x17=153 1+5+3=9.......spooky.

but you have to work out 9x17 first, can't do it using my easy method of going one lower and adding up to make 9 "

It's not a method, it's just one of the sequential patterns that emerge when you learn your tables by rote.

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By (user no longer on site)
over a year ago

Bakers could never count - Bakers Dozen

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By (user no longer on site)
over a year ago

[Removed by poster at 22/10/13 00:46:07]

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By (user no longer on site)
over a year ago


"But why were there 12 thingys in a whatsit? Who decided we needed 12 of them? "

That's easy... 12 thingys make a whatsit and 4 whatsits make a doberry so when you revert this to decimals it simplifies itself to the lowest common denominator ( give or take 1 or 2 decimal places ) me thinks lol

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By *exxifun5Couple
over a year ago

NORWICH

Omg maths being my weakest subject (and I could never learn my times tables ) all these numbers in this thread have made me all smooshy !!! I just see numbers and I start to stress and all common sense leaves me xx tab xx

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By (user no longer on site) OP   
over a year ago


"But why were there 12 thingys in a whatsit? Who decided we needed 12 of them?

That's easy... 12 thingys make a whatsit and 4 whatsits make a doberry so when you revert this to decimals it simplifies itself to the lowest common denominator ( give or take 1 or 2 decimal places ) me thinks lol "

you had to go and complicate it with your decimals didn't you. Now I'm lost

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By (user no longer on site)
over a year ago

I did a gcse in maths a few years ago to sort out the gremlins x loved it x

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By (user no longer on site)
over a year ago


"There was a time - several decades ago now - when the reason for learning the 12 times table was obvious. As a country using imperial measurements, we were all measuring in feet and inches and paying in shillings and pence, so multiplying by 12 was a common, everyday experience.

But for today's children this is all ancient history. Yes, we do still count eggs in dozens, and a lot of people - including most Americans - do still work in inches, but that's hardly justification for spending hours swotting those extra tables.

And yet, there's still a case for learning your "twelves", but the reason is to do with discovering patterns and building a confidence in handling numbers.

Once children begin to get comfortable multiplying numbers larger than 10, they start to get a feel for big multiplications. Knowing your 11 and 12 times tables can introduce intriguing patterns that might be missed if you stop at 10.

Much of the 11 times table is trivial to learn: 2 times 11 is 22, 8 times 11 is 88. And even when you get beyond 12, there are nice patterns to discover.

Want to multiply 11 by 23? Just take the two digits 2 and 3, add them together (makes 5) and put that number in the middle - 253. What about 36 x 11? Again, split the 3 and the 6 and put their sum (9) in the middle - 396. Lovely - though take care, if the two digits add to more than 9, this nifty trick doesn't work so neatly. 58 x 11... well 5+8 = 13, but the answer isn't 5138, that "1" actually represents a 100, and needs to be added to the 5 to give the answer 638.

There's a pattern that begins with 11 x 11, too. Multiply those two numbers together and you get 121. How about 111 x 111? The answer is 12321. Care to guess what 1111 x 1111 is? Yes, 1234321.

Meanwhile multiplying by 12 becomes much simpler when you realise it's the same as multiplying a number by 10 and then adding on double the start number. So 12 x 12 is 10 x 12 (=120) and then add 2 x 12 (=24) to give 120+24 = 144. This rule doesn't stop at your tables - 12 x 61 is the same as 10 x 61 (=610) plus 2 x 61 (=122) and if you can add 610 + 122 in your head you have the right answer, 732.

Do you need to memorise the answer to 12 x 12? Well, not really. As long as you know the strategy for working it out, you can get there almost as quickly by recalculating it in your head. But, of course, if you do a calculation often enough, it will become embedded in your memory, which will speed things up on those occasions when you need the answer.

Why stop at 12? You can continue to 13, 14… all the way up to 20 times table, as I believe happens in some countries. But hang on, if you understand your basic times tables up to 10, then you have the essential tools you need for working out, say, 19 x 14. And if you spend too much time rote learning the answers to these questions then you're going to miss out on time spent understanding how numbers work.

And it's understanding patterns and solving problems that maths is really all about.

"

Far out!!!

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By (user no longer on site)
over a year ago

I'm shocking with numbers

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By (user no longer on site)
over a year ago


"I'm shocking with numbers "

Lolz - I wasn't going to bother reading this thread but thanks to that particular post - I'm really glad I did now!!

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