A man takes certain time to row 8 km downstream. But when he swims upstream for the same time, he can cover 6 km. If he rows a distance of 96 km upstream and comes back in 28 hours, then find the rate of the stream ?
Assume x hours be the time taken to move 8 km downstream. then x will be the time taken to cover 6 km upstream.
Total distance travelled = 96 km
Downstream speed = 8/x km/hr
Time taken to row 96 km downstream = 96 / (8/x) = 12x hrs (time = speed / distance )
Upstream Speed = 6/x km/hr
Time taken to row 96 km upstream = 96 / (6/x) = 16x hrs
Time taken to return back is 28 hrs
Total Time taken = Time taken to row downstream + Time taken to row upstream
28 = 12x + 16x
28 = 28x
x = 1
Substituting x = 1 we get,
Downstream Speed = 8 km/hr and Upstream Speed = 6 Km/hr.
Rate of stream = 8 - 6 / 2 = 1 Km/hr
Back To Top