Answer :

AndyBryer
To find this we need to divide 56 by the sum of 5 and 3 (8) and then multiply that answer by each of 5 and 3.
Therefore:
56/8=7
7*5=35
7*3=21
35:21
As ratio is 5:3, in total there are 8 different bits.

Therefore divide 56 by 8, to get 7.

Each bit is worth 7, so each side of the ratio can be multiplied by 7.

This means you get it to be 35:21