Boats and Streams

A man can row at 5 km/hr in still water. If the river is running at 1 km/hr, it takes him 75 min to row to a place and come back. How far is the place ? 

A boat covers a certain distance downstream in 1 hour, while it comes back upstream in 1 1/2 hours. If the speed of the stream be 3 kmph, what is the speed of the boat in still water?  

A boat can travel with a speed of 13 km/hr in still water. If the speed of the stream is 4 km/hr, find the time taken by the boat to go 68 km downstream. 

The speed of a boat in still water is 15 km/hr and the rate of current is 3 km/hr. The distance travelled downstream in 12 minutes is:

In one hour, a boat goes 11 km/hr along the stream and 5 km/hr against the stream. The speed of the boat in still water (in km/hr) is:

A motorboat whose speed is 15 km/hr in still water goes 30 km downstream and comes back in 4 hrs and 30 mins. The speed of the stream is: 

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: 

A man can row 6 km/ hr in still water. If it takes him twice as long to row up, as to row down the river, then the rate of current in the stream is:

A boat running downstream covers a distance of 16 km in 2 hours while for covering the same distance upstream, it takes 4 hours. What is the speed of the boat in still water?

A man rows to a place 48 km distant and come back in 14 hours. He finds that he can row 4 km with the stream in the same time as 3 km against the stream. The rate of the stream is: