A and B start at the same time with speeds of 40 km/hour and 50 km/hour respectively.
If in covering the journey, A taken 15 minutes longer than B, the distance of the journey is :

Answer: C. 50 km

Suppose distance of journey = x km
Time taken by A to Cover x km = x/40 hours.
Time taken by B to Cover x km = x/50 hours.
By Hypothesis,
x/40 - x/50  = 15/60  or  x/200= 15/60
x = (15 x 20)/6
= 50 km