Boats and Streams Exercise 1

A boat travels upstream from B to A and downstream from A to B in 3 hours. If the speed of the boat in still water is 9 km/hr and the speed of the current is 3 km/hr, the distance between A and B is

A man can row 4.5 km/hr in still water and he finds that it takes him twice as long to row up as to row down the river. Find the rate of the stream.

The speed of a boat in still water is 4 km/hr and the speed of current is 2 km/hr. If the time taken to reach a certain distance upstream is 9 hours, the time it will take to go to same distance downstream is

A man can row upstream 36 km in 6 hours. If the speed of man in still water is 8 km/h, find how much he can go downstream in 10 hours.

A man makes his upward journey at 16 km/h and downward journey at 28 km/h. What is his average speed?

A man can swim with the stream at the rate of 3 kmph and against the stream at the rate of 2 kmph. How long will it take him to swim 7 km in still water?

A man can row with the stream at 6 km per hour and against the stream at 4 km an hour. Find the man’s rowing speed in still water and the speed of the current.

Twice the speed of a boat downstream is equal to thrice the speed upstream. The ratio of its speed in still water to its speed in current is:

A man can row 3/4 of a km against the stream in 11¼ minutes and return in 7¼ minutes. Find the speed of the man in still water :

A man can row 4 km/h in still water and he finds that it takes him twice as long to row up as to row down the river. Find the rate of stream.

A man can row 6 km/hr. in still water. It takes him twice as long to row up as to row down the river. Find the rate of stream

Speed of a speed-boat when moving in the direction parallel to the direction of the current is 16 km/hr. Speed of the current is 3 km/hr. So the speed of the boat against the current will be (in km/hr)

A boat has to travel upstream 20 km distance from point X of a river to point Y. The total time taken by boat in travelling from point X to Y and Y to X is 41 minutes 40 seconds. What is the speed of the boat?

A boat covers a distance of 30 km downstream in 2 hours while it take 6 hours to cover the same distance upstream. If the speed of the current is half of the speed of the boat then what is the speed of the boat in km per hour?

A boy rows a boat against a stream flowing at 2 kmph for a distance of 9 km, and then turns round and rows back with the current. If the whole trip occupies 6 hours, find the boy’s rowing speed in still water.

Two boats, travelling at 5 and 10 kms per hour, head directly towards each other. They begin at a distance 20 kms from each other. How far apart are they (in kms) one minute before they collide?

There is a road besides a river. Two friends Ram and Shyam started from a place A, moved to a temple situated at another place B and then returned to A again. Ram moves on a cycle at a speed of 12 km/h, while Shyam sails on a boat at a speed of 10 km/h. If the river flows at the speed of 4 km/h, which of the two friends will return to place A first?

A man wishes to cross a river perpendicularly. In still water, he takes 4 minutes to cross the river, but in flowing river he takes 5 minutes. If the river is 100 metres wide, then the velocity of the flowing water of the river is:

Speed of a speed-boat when moving in the direction perpendicular to the direction of the current is 16 km/h. Speed of the current is 3 km/h. So the speed of the boat against the current will be (in km/h)

A ship 156 km away from the shore springs a leak, which admits 2⅓ metric tons of water in 6½ mins., but the pumps throw out 15 metric tons of water in 1 hour. 68 metric tons would suffice to sink the ship. Find the average rate of sailing so that she may just reach the shore as she begins to sink.