A boat rows downstream covers a distance of 20 km in 2 hrs while it covers the same distance upstream in 5 hrs. Then speed of the boat in still water is : 

The speed of the current is 5 km / hour. A motorboat goes 10 km upstream and back again to the starting point in 50 minutes. The speed (in km / hour) of the motorboat in still water is: 

A man rows 12 km in 5 hours against the stream and the speed of current being 4 kmph, What time will be taken by him to row 15 km with the stream? 

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 : 

A motorboat covers a certain distance downstream in a river in 3 hours. It covers the same distance upstream in 3 and half an hour. If the speed of the water is 1.5 km / h, then the speed of the boat in still water is: 

The speed of a boat downstream is 15 km/hr. and the speed of current is 3 km/hr. Find the total time taken by the boat to cover 15 km upstream and 15 km downstream. 

The speed of the motorboat in still water is 45 kmph. If the motorboat travels 80 km along the stream in 1 hour 20 minutes, then the time taken by it to cover the same distance against the stream will be: