A man can row 4 km/h in still water. If the river flows at 2 km/h, how long will it take him to row 10 km upstream?
Q1. A man can row 4 km/h in still water. If the river flows at 2 km/h, how long will it take him to row 10 km upstream?
Answer: 5 hours
Explanation: Speed upstream = Speed in still water - Speed of river = 4 - 2 = 2 km/h. Time = Distance / Speed = 10 / 2 = 5 hours.