A boat goes 10kms an hour in still water, but takes twice as much time in going the same distance against the current. The speed of the current (in km/hr) is 

The speed of a boat in still water is 10 km/hr. It covers (upstream) a distance of 45 km in 6 hours. The speed (in km/hr) of the stream is : 

Speed of a boat in still water is 6 km/hr and speed of the current is 2 km/hr. If boat takes four hours more in upstream than in the downstream to cover ‘D’ km, then find time take by boat to cover ‘D’ km in still water?

A man can row downstream at a speed of 15 km/h and upstream at 11 km/h. Find his speed in still water and the speed of the current, respectively. [Give both your answers in km/h]

A motorboat whose speed is 20 km/h in still water takes 30 minutes more to go 24 km upstream than to cover the same distance downstream. If the speed of the boat in still water is increased by 2 km/h, then bow much time will it take to go 39 km downstream and 30 km upstream?

A Man rows to a place 63 km far and comes back in 16 hours. He finds that he can row 18 km with the flow in the same time taken to row 14 km against the flow. What is the speed of the stream?

A boat moves 25km upstream and 39km downstream in 8 hours. It travels 35km upstream and 52km downstream in 11 hours. What is the speed of the stream if it travels at a uniform speed?

A boat starts travelling from point P, travels to point Q then returns to point P. The boat takes 12 hours to complete the journey. The speed of the stream is 5 km/hour and the speed of the boat in still water is 10 km/hour. What is the distance between P and Q?