Question
When travelling downstream, a boat takes 5 hours to
travel 240 km. If the speed of the stream is (5/8)th of downstream speed of the boat, then find the time taken by the boat to cover 360 km in still water.Solution
Downstream speed of the boat = 240/5 = 48 km/hr Speed of the stream = 48 x (5/8) = 30 km/hr So, speed of the boat in still water = 48 – 30 = 18 km/hr Required time taken = 360/18 = 20 hours
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