App Logo

No.1 PSC Learning App

1M+ Downloads
A motor-boat, travelling at the same speed, can cover 25 km upstream and 39 km downstream in 8 hours. At the same speed, it can travel 35 km upstream and 52 km downstream in 11 hours. The speed of the stream is

A2 km/hr

B3 km/hr

C4 km/hr

D5 km/hr

Answer:

C. 4 km/hr

Read Explanation:

25 up+39 down = 8 hours. 35 up +52 down = 11 hours Solving 13 down-stream in 1 hours and 5 up-stream in 1 hour. Speed of stream 13-5/ 2 = 4km/hr


Related Questions:

A boatman can go certain distance downstream in 2 hrs. and upstream same distance in 3 hrs. If the stream flow at the speed of 4 km/h, find the speed of boat in still water.
The total time by the boat to cover 72 km upstream and 180 km downstream in 16 hours. The total time taken by the same boat to cover 108 km upstream and 126 downstream in 16 hours. If the sum of the upstream speed and downstream speed of the boat is 30 km, then find the speed of the stream.
Two boats A and B start towards each other from two places, 108 km apart. Speed of the boat A and B in still water are 12km/hr and 15km/hr respectively. If A proceeds down and B up the stream, they will meet after.
A boat takes thrice the time in moving a certain distance upstream than downstream. Find the ratio of speed of boat in still water to that of speed of current.
A man can row 30 km down stream and return in a total of 8 hours. If the speed of the boat in still water is four times the speed of the current, then the speed of the current is