Two men, A and B, run a 4 km race on a circular course of 1/4 km. If their speeds are in the ratio of 5:4, how often doe's the winner pass the other?
Once
Twice
Thrice
Four times
When A runs 5 rounds, B runs 4 rounds (ratio of speeds) A passes B each time A has run 5 rounds or 5 x 1/4 = 5/4km. = 1 1/4km 1 1/4km is contained in 4 km 3 times. Hence A passes B thrice.