Let the speed of a boat in still water be $u$ km/hr and the speed of the water current in a river be $v$ km/hr. If a man rows distance $D$ down stream and same distance upstream, then average speed of total journey is

It is currently 9:40 AM. What will be the time in next 610 hours?

In a race of 800 m, A beats B by 80 m and in a race of 600 m, B beats C by 40 m. Then A will beat C in a race of 1000 m by :

A man rows downstream 30 km and upstream 20 km. If he takes 5 hours to cover each distance, then the speed of stream is

In a 900 meters race, A gives B a start of 150 meters and defeats him by 50 seconds. If the speed of A is 4.5 m/sec, then speed of B is:

A person can row a motor boat in still water at the rate of 12 km/hr. It takes him thrice as long to row upstream of a river as to row downstream of the same river. The speed of the stream is :

Two runners, Ajay and Vijay complete a 600 m race in 38 seconds and 48 seconds respectively. By how many meters will Ajay defeat Vijay?