Boats and Stream

31 A man can row against the current three-fourth of a kilometre in 15 min and returns same distance in 10 min, then ratio of his speed to that of current is

32 A person can row a certain distance downstream in 6 hours and return the same distance in 9 hours. If the stream flows at the rate of 2 4 km /h, still water. find how far he can row in an hour in

33 What time will be taken by a boat to cover a distance of 64 km along the stream, if speed of boat in still water is 12 km/h and speed of stream is 4 km/h?

34 A man can row 7 —2 km/hr in still water. If in a river running at 1.5 km/hr, it takes him 50 minutes to row to a place and back, how far off is the place?

35 A man can row at 5 km/h in still water and the velocity of the current is 1 km/h. It takes him 1 hour to row to a place and back. How far is the place ?

36 A boat goes 48 km downstream in 20 h. It takes 4 h more to cover the same distance against the stream. What is the speed of the boat in still water?

37 A boat covers a certain distance downstream in 1 hour, while it comes back in 1 hours. If the speed of the stream be 3 kmfhr, what is the speed of the boat in still water?

38 A boat's speed in still water is 5 km/h. While river is flowing with a speed of 2 km/h and time taken to cover a certain distance upstream is 2 h more than time taken to cover the same distance downstream. Find the distance:

39 Speed of motorboat in still water is 45 km/h. If the motorboat travels 80 km along the stream in 1 h 20 min, then the time taken by it to cover the same distance against the stream will be

40 Sameer can row a certain distance downstream in 24 h and can come back covering the same distance in 36 h. If the stream flows at the rate of 12 km/h, find the speed of Sameer in still water: