Boats and Streams

A steamer can go 12 km in still water in 25 minutes. One day, it went 11.25 km upstream and returned the same distance in downstream. If the difference between the time taken to travel upstream and downstream was 12.5 minutes, then what was the speed of stream in km per hour?

• 7.2

• 5.4

• 6.3

• 4.5

If the upstream speed of a boat is 50% less than the downstream speed of the boat and if a object is thrown in the river it covers 100m in 50 sec, then how much distance boat can cover in still water in 5 hours?

• 900 m

• 100 m

• 120 m

• 108 m

A boat goes a certain distance upstream and comes back downstream to the starting point in 144 min. If the speed of the boat in still water becomes 66.67% of the original, time taken for the same journey will be 224 min. What is the ratio of the speed of boat in still water and speed of current?

• 7:1

• 6:1

• 5:3

• 7:2

The speed of current is 5 km/h. What will be the respective downstream speed and upstream speed of a boy rowing a boat, if one third of the distance covered going downstream in a certain time is equal to the distance covered going upstream in the same time.

• 15 kmph, 5 kmph

• 20 kmph, 10kmph

• 18 kmph, 8 kmph

• 24 kmph, 14 kmph

There are 3 points P, Q and R in a straight line, such that point Q is equidistant from points P and R. A man can swim from point P to R downstream in 24 hours and from Q to P upstream in 16 hours. Find the ratio of speed of man in still water to speed of stream?

• 5 : 1

• 6:1

• 5:3

• 7:1

A boat takes 12 hours to cover an upstream distance of 48 km and 6 hours to come back same distance in downstream. What is the speed of boat in steel water?

• 6 kmph

• 8 kmph

• 4 kmph

• 10 kmph

Rohit and Mohit are coming via boat towards each other from the two banks of a river. They meet after three hours from start. If speed of both boats in still water is 6 kmph and river is flowing from Mohit towards Rohit, then find the distance between two banks.

• 18 km

• 36 km

• 24 km

• 48 km

A motorboat, whose speed in 15 km/hr in still water goes 30 km downstream and comes back in a total of 4 hours 30 minutes. The speed of the stream (in km/hr) is

• 3 kmph

• 5kmph

• 4kmph

• 2kmph

A boat running upstream takes 8 hours 48 minutes to cover a certain distance, while it takes 4 hours to cover the same distance running downstream. What is the ratio between the speed of the boat in still water and speed of the water current respectively?

• 2:1

• 3:2

• 4:5

• 8:3

A boat takes 9hr to travel a distance upstream and takes 6hr to travel the same distance downstream. If the speed of the boat in still water is 4 kmph, then what is the velocity of the stream?

• 0.8

• 0.3

• 0.7

• 0.4