In a river, a man takes 3 hours in rowing 3 km upstream or 15 km downstream. What is the speed of the current?
Q1. In a river, a man takes 3 hours in rowing 3 km upstream or 15 km downstream. What is the speed of the current?
Answer: 2km/hr
Explanation: Upstream speed = 3/3 = 1 km/hr; downstream speed = 15/3 = 5 km/hr. Current speed = (5−1)/2 = 2 km/hr.