In a 100-m race, A beats B by 20 m and B beats C by 20 m. By how much distance does A beat C.

36 m

According to the question,

When A covers 100 m, B covers 80 m

And when B covers 100 m, C covers 80 m

So, the distance ratio of A to B and B to C are 10 : 8 and 10 : 8

A : B : C = 100 : 80 : 64

So, A beats C by 100 - 64

= 36 m

So ,  A beats C by 36 m