Question

In a 1000 metre race, A beats B by 30 seconds and B beats C by 20 seconds. By how much did A beat C?
A.50 seconds
B.48 seconds
C.52 seconds
D.Can't be determined

Answer 1

A beats B by 30seconds

let A takes T1 seconds

let B takes T2 seconds

T1-T2=30

let C takes T3 seconds

T2-T3=20

add these equations,we get

T1-T3=20+30=50 seconds

Answer 2

Ans: 50 seconds

step by step explanation:

let A takes x seconds to win

B takes. Y seconds

A beats B by 30 seconds

x - y = 30seconds

let C takes z seconds

B beats C by 20 seconds

y -z = 20 seconds

A beats C by x - y + y - z = 30 +20 = 50sec