Maths help!
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Maths help!
Hello all,
This is a multiple choice maths question.
Which of the fraction is closest to ¼
11/40, 16/60, 21/80, 26/100, 31/120.
How can a 10 year old do in shortest time, any tips much appreciated.
Thank-you!
This is a multiple choice maths question.
Which of the fraction is closest to ¼
11/40, 16/60, 21/80, 26/100, 31/120.
How can a 10 year old do in shortest time, any tips much appreciated.
Thank-you!
Re: Maths help!
If you look at each fraction the numerator (top number) is always one more than the number which would make the fraction an exact quarter.
(1/4 = 10/40 = 15/60 = 20/80 = 25/100 = 30/120)
So it should then be clear that 31/120 is closest to a quarter because it only differs by 1/120, which is smaller than 1/100, 1/80 etc.
(1/4 = 10/40 = 15/60 = 20/80 = 25/100 = 30/120)
So it should then be clear that 31/120 is closest to a quarter because it only differs by 1/120, which is smaller than 1/100, 1/80 etc.
Re: Maths help!
Could be wrong but I'm thinking it's the last, biggest one. Only because, and trying to do it quickly here, they are all 4 over, but the larger the number, the less percent that 4 off represents. So the first one is 44, that's 10% over the 40 you are aiming for, whereas in the last, 4 over is only, ooh, 3% over the target?
I am sure there is a more technical way, but tellme if I'm right! Probably not!
I am sure there is a more technical way, but tellme if I'm right! Probably not!
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Re: Maths help!
Thank-you for all responses!
Yes proud_dad, that makes sense.
This question is from The Perse School specimen paper
Yes proud_dad, that makes sense.
This question is from The Perse School specimen paper