Question

Hi which fraction is bigger 5/8 or 11/20 and why ?

Answer 1

so to add fractions, the bottom number (denomenator) must be the same

we can change the fractions without really doing anything to them by using this concept: 1/2=4/8 because 4/8=1/2 times 4/4 (and 4/4=1)

so we list the number that 8 and 20 can multiply into by factoring them so

8=2*2*2
20=2*2*5
so we group the number so
2*2*2*5 or 40

multiply 5/8 by 5/5 and get 25/40
multiply 11/20 by 2/2 and get 22/40
25/40>22/40 so 5/8 is bigger

Answer 2

The best thing to do for this question is to find a common denominator, and the best way to do this is to list all of the multiples and find the smallest common one.
8- 8, 16, 24, 32, 40, 48
20- 20, 40, 60

In this, 40 is the lowest, so you have to multiply 5/8 by 5 at the top and bottom, and this gives you 25/40. You have to multiply the second fraction by 2, and this becomes 22/40.
Therefore, the larger fraction is 5/8.
The alternative method is to turn them into decimals and compare them this way. 5/8= 0.625 & 11/20= 0.55

Hope this helps