Question
When travelling downstream, a boat takes 6.25 hours to
travel 225 km. If the speed of the stream is (1/3)rd of downstream speed of the boat, then find the time taken by the boat to cover 240 km in still water.Solution
Downstream speed of the boat = 225/6.25 = 36 km/hr Speed of the stream = 36 x (1/3) = 12 km/hr So, speed of the boat in still water = 36 – 12 = 24 km/hr Required time taken = 240/24 = 10 hours