A boat covers 35 km downstream in 2 h and covers the same distance upstream in 7 h. Find the speed (in km/h) of the boat in still water.  

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

In a river the distance between two points is 80 km. A boat which rows 13 km/h in still water goes downstream from the first point to the second and returns upstream to starting point in 13 hrs., then find the speed of current. 

A person swims a distance of 28 km. in the direction of stream in 5 hours and a distance of 13 km. in 5 hours against the stream. What is the velocity of the stream?

A boat goes 12 km downstream and comes back to the starting point in 3 hours. If the speed of the current is 3 km/hr, then the speed (in km/hr) of the boat in still water is : 

A boat running downstreams covers a distance of 30 kms in 2 hours. While coming back the boat takes 6 hours to cover the same distance. If the speed  of the current is half that of the boat, what is the speed of that boat in kmph?

A man swims downstream distance of 15 km in 1 hour. If the speed of the current is 5 km/ hr, the time taken by the man to swim the same distance upstream is : 

A man can row at a speed of $$4{1\over 2}$$km/hr in still water. If he takes 2 times as long to row a distance upstream as to row the same distance downstream, then the speed of stream (in km/hr) is :