Two motor cyclists meet after 2 hours if they drive from 100 km apart in the same direction, but they meet in 1 hour if they drive in the opposite direction.
The ratio between the speed of faster motor cyclist and the other one is :

Answer: B. 3 : 1

Suppose, speeds of two motor cyclists are x km/hr and y km.hr ( x>y ).
By hypothesis,
2x = 100 + 2y  or  x - y = 50  and x + y = 100
Solving x = 75, y = 25
hence, ratio of their speeds = x : y = 75 : 25 = 3 : 1