Ravi row to a place 45km distant and back in 20 hours. He finds that he can row 12km with stream in the same time as 4km against the stream ,then the speed of the stream is:

In a 10 km race, A, B and C each running at uniform speed get the gold, silver and bronze medals respectively. If A beats B by 1 km and B beats C by 1 km, then by how many meters does A beat C?

A man rows 15 km upstream in 5 hours and 25 km downstream in 5 hours each time, then the speed of the stream is

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

In a 700 m race, the ratio of speeds of two participants A and B is 5:6. If A has a start of 150 m, then the distance by which A wins the race is:

A runs 3 times as fast as B. If A gives B a start of 30 meters, how far must the goal on the race course be so that A and B reach it at the same time?

Mr. X runs 5 times as fast as Mr. Y. If Mr. X gives Mr. Y a start of 80 meters, how far must the goal on the race course be so that Mr. X and Mr. Y reach it at the same time?