Speed of a boat in still water is 9 km/hr. It goes 12 km downstream and comes back to the starting point in three hours. What is the speed of water in the stream?

Let the speed of the boat = 9km/hr Speed of current = x km/hr Speed upstream = (9 – x) km/hr Speed downstream = (9 + x) km/hr Time upstream + time downstream = 3 hours Time = distance/(speed ) 12/(9-x)+ 12/(9+x) = 3 x = 3 km/hr

- The speed of a boat in still water is 8 km/hr and speed of current is 3 km/hr. If time taken to cover a certain distance upstream is 11 hours, then how long will the boat take to cover the same distance downstream?
- A boat goes 50 km in upstream in 5 hours and takes 3 hours to complete a distance of 18 km in downstream. Find the speed of boat in still water.
- Find the total distance covered by boat in each upstream and downstream in 5 hours if the speed of boat in still water and speed of current is 25 km/h and 6 km/h respectively?
- A man rows upstream 10 km and downstream 15 km taking 5 hours each. Find the speed of current.
- A man can row upstream at 18 km/hr and downstream at 24 km/hr. Find the man’s rate in still water and the rate of the current.
- The speed of a motorboat in still water is 50 km/hr. If the motorboat travels 120 km along the stream in 1 hour 30 minutes, then the time taken by it to cover the same distance against the stream will be
- When travelling downstream, a boat takes 5.25 hours to travel 252 km. If the speed of the stream is (3/8)
^{th}of downstream speed of the boat, then find the time taken by the boat to cover 300 km in still water. - Sumit can swim 12 km upstream and 16 km downstream in 5 hours. If ratio of speed of stream to that of speed of Sumit in upstream is 1:2, then find the speed of Sumit in still water.
- A Motorboat takes 24 hours for travelling downstream from a point A to point B and coming back to point C, which is 1/3rd of distance between A and B. if the speed of the stream is 15 km/hr and the speed of the Motorboat in still water is 30 km/hr, then find out the distance between B and C?
- A man can row 32 km/hr in still water. It takes him thrice as long to row up as to row down the river. Find the rate of the current.

More Boats and streams Questions

×