A man goes downstream with a boat to some destination and returns upstream to his original place in ......

A man goes downstream with a boat to some destination and returns upstream to his original place in 5 hours . If the speed of the boat in still water and the stream are 10 km/hr and 4 km/hr respectively,the distance of the destination from the starting place is :

Speed of the boat in sill water= 10 km/h
Speed of the steam = 4 km/h
Thus, Downstream speed = 6 km/h
Let Distance = M km.
M/14 + M/6 = 5 hours
(3m + 7M)/42 = 5
10M = 42 × 5
M = 42 × 5/10 = 21 km

By: Manpreet kaur