1.  A runs 1 times as fast as B. If A gives B a start of 80 m, how far must the winning post be so that A and B might reach it at the same time?
A. 200 m
B. 300 m
C. 270 m
D. 160 m

Answer: Option A

Explanation:

Ratio of the speeds of A and B = 5 : 1 = 5 : 3.
3

Thus, in race of 5 m, A gains 2 m over B.

2 m are gained by A in a race of 5 m.

80 m will be gained by A in race of 5 x 80 m
2
= 200 m.

Winning post is 200 m away from the starting point.