Ratio of time taken by a sailor to cover some distance upstream and downstream is 4 : 1. If speed of stream is 4.5 km/hr. Then find out speed of boat? 

If the speed of a boat in still water is 20 km/hr and the speed of the current is 5 km/hr, then the time taken by the boat to travel 100 km with the current is : 

A man rows to a place 35 km in distance and back in 10 hours 30 minutes. He found that he can row 5 km with the stream in the same time as he can row 4 km against the stream. Find the rate of flow of the stream? 

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 : 

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: 

A boat covers 24 km upstream and 36 km downstream in 6 hours, while it covers 36 km upstream and 24 km downstream in $$6{1\over 2}$$ hours. The speed of the current 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 : 

A boat moves downstream at the rate of 1 km in $$7{1\over 2}$$ minutes and upstream at the rate of 5 km an hour. What is the speed of the boat in the still water?