A boat travels 20 km upstream in 4 hours and 20 km downstream in 2 hours. Find the speed of the boat in still water.

Question

Accepted Answer

(B) 7.5 km/h. Explanation: Upstream speed = 20/4 = 5 km/h. Downstream speed = 20/2 = 10 km/h. Boat speed = (10+5)/2 = 7.5 km/h.