A boat moves downstream at the rate of 1 km in $$7{1\over 2}$$ minutes and upstream at the rate of 5 km an hour. What is the speed of the boat in the still water?  

A boat covers a certain distance against the stream in 9 hours 36 min and it covers the same distance along the stream in 6 hours. What is the ratio of the speed of the boat in still water to that of the stream?

On a river, Q is the mid-point between two points P and R on the same bank of the river. A boat can go from P to Q and back in 12 hours, and from P to R in 16 hours 40 min. How long would it take to go from R to P?

If the speed of a boat in still water is 20 km/hr and the speed of the current is 5km / hr, then the time taken by the boat to travel 100km with the current is

A man can row upstream at 12 km/hr and dowstream at 18 km/hr. The man's rowing speed in still water is:

The water in a river is flowing at the rate of 4 km/hr. If the width and depth of the river is 8m and 4m respectively, then how much water will enter the sea in 15 minutes.

Speed of a along and against the current are 14 km / hr and 8 kms/hr respectively. The speed of the current is: