A man rows down a river of length 24 km in 4 hours with the stream and returns in 8 hours. What is the speed of the boat in still water?

Explanation

Given: Distance (one way) = 24 km Time taken downstream = 4 hours Time taken upstream = 8 hours We need speed of boat in still water. Formula Used: Distance Speed = ​ Time ​ Downstream speed = Boat speed + Stream speed Upstream speed = Boat speed – Stream speed Downstream speed + Upstream speed Boat speed in still water = ​ 2 ​ Solution: 24 Downstream speed = = 6 km/h​ 4 ​ 24 Upstream speed = = 3 km/h​ 8 ​ 6+3 9 Speed of boat in still water = = = 4.5 km/h​ 2 2 ​ ​ The speed of the boat in still water = 4.5 km/h