FabSwingers.com forum: Maths Hacks

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

I'm rubbish with numbers but heard this great maths hack on the radio this morning.

Percentages work in reverse. Might just be me that didn't know this but, for example, if you need to know 8% of 25 you can do 25% of 8 instead. Or 62% of 50, just work out 50% of 62 instead etc etc.

Any others to help poor maths-challenged souls like me?

(PS. I am aware this is not a very sexy thread

)

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By *nto My ArmsMan
over a year ago

Herts/London

I like the 9 times table on your fingers hack.

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By *ed-monkeyCouple
over a year ago

Hailsham

You'll be proving Fermat's last theorem in no time now

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

"I'm rubbish with numbers but heard this great maths hack on the radio this morning.

Percentages work in reverse. Might just be me that didn't know this but, for example, if you need to know 8% of 25 you can do 25% of 8 instead. Or 62% of 50, just work out 50% of 62 instead etc etc.

Any others to help poor maths-challenged souls like me?

(PS. I am aware this is not a very sexy thread

)

Taking your socks of can help with counting on your toes

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By *ntrigued32Couple
over a year ago

Nottingham

You just keep talking numbers M.I.A

it will be a very sexy thread!

And I agree with the 9 times table hack I teach my kids that way

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

For an estimated Celsius to Fahrenheit, just times it by 2 and add 30

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

Sure numbers can be sexy!

I give you:

36-24-32

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

I can't work out any of the finger trick ones! They did try explaining how to do one on that show too but I got muddled up half way through!

I'm genuinely not that stupid

but numbers are so not my thing.

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

"I like the 9 times table on your fingers hack.

The digits of the 9 times table always add up to 9.

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By *ed-monkeyCouple
over a year ago

Hailsham

"Sure numbers can be sexy!

I give you:

36-24-32

36-24-32? ... I make that -20

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By *ntrigued32Couple
over a year ago

Nottingham

"I can't work out any of the finger trick ones! They did try explaining how to do one on that show too but I got muddled up half way through!

I'm genuinely not that stupid

but numbers are so not my thing. "

For eg 4x9 hold both hands out with fingers outstretched then count 4 and drop that finger, you will be left with 3 fingers in one side of it and six fingers the other side 36

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By *hunky GentMan
over a year ago

Maldon and Peterborough

You can work out if any number is a multiple of nine by adding the digits.

ie 81: 8+1=9

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

69 is not prime but is the product of two that are prime ... that's about as sexy as I can make maths

... I leave now

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By *rviennaCouple
over a year ago

Kent

Always remember sohcahtoa, never ever needed it!

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

"I can't work out any of the finger trick ones! They did try explaining how to do one on that show too but I got muddled up half way through!

I'm genuinely not that stupid

but numbers are so not my thing.

For eg 4x9 hold both hands out with fingers outstretched then count 4 and drop that finger, you will be left with 3 fingers in one side of it and six fingers the other side 36

D. "

Ah ha, I get that actually. What do you do if you're multiplying more than 10 though? The nine times table I'm good with up to 10 already as the digits in the answers always add up to 9. See, I always need a hack haha

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

"Always remember sohcahtoa, never ever needed it!"

I still use BODMAS too although a maths teacher told me not to, I'm not sure why

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By *partharmonyCouple
over a year ago

Ruislip

There's a good YouTube channel called Tecmath which is full of this sort of thing.

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By *ntrigued32Couple
over a year ago

Nottingham

"I can't work out any of the finger trick ones! They did try explaining how to do one on that show too but I got muddled up half way through!

I'm genuinely not that stupid

but numbers are so not my thing.

For eg 4x9 hold both hands out with fingers outstretched then count 4 and drop that finger, you will be left with 3 fingers in one side of it and six fingers the other side 36

I don’t know that bit

my kids only single numbers

but I’m guessing the same trick can be used by adding 90

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By *rviennaCouple
over a year ago

Kent

"There's a good YouTube channel called Tecmath which is full of this sort of thing. "

This could be my new porn!

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By *eastAndTheHarlotCouple
over a year ago

Hartlepool

Not really a hack as such but learning to do maths on paper really helps if you're ever without a calculator.

Also learn how to do % on a calculator because so many adults can't. Just divide the number by 100 then times it by whatever % you want to find.

23.5 % of X would be X divided by 100 then times by 23.5

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

"Not really a hack as such but learning to do maths on paper really helps if you're ever without a calculator.

Also learn how to do % on a calculator because so many adults can't. Just divide the number by 100 then times it by whatever % you want to find.

23.5 % of X would be X divided by 100 then times by 23.5"

That one is my saving grace, people always overcomplicate how to do percentages using a calculator. I do it the same way as you.

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By *hunky GentMan
over a year ago

Maldon and Peterborough

"Not really a hack as such but learning to do maths on paper really helps if you're ever without a calculator.

Also learn how to do % on a calculator because so many adults can't. Just divide the number by 100 then times it by whatever % you want to find.

23.5 % of X would be X divided by 100 then times by 23.5

That one is my saving grace, people always overcomplicate how to do percentages using a calculator. I do it the same way as you. "

Or just times the number by 0.235 (23.5%)

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

"Sure numbers can be sexy!

I give you:

36-24-32

36-24-32? ... I make that -20

Can't argue with that!

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

"Sure numbers can be sexy!

I give you:

36-24-32

36-24-32? ... I make that -20

Can't argue with that!

Though you have assumed I'm using a decimal number system

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By *andlingswingersCouple
over a year ago

Woodbridge

Just memorise your times tables. You don't have to "understand" them (whatever that's supposed to mean), so long as you just know them. Parrot fashion.

And yes, one of us does private Maths tuition.

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By *apascouseMan
over a year ago

Liverpool

As someone who went through 5 years of maths higher education, this has me stumped

I never even noticed

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