A steamer goes downstream from one point to another in 9 hours. It covers the same distance upstream in 10 hours. If the speed of the stream be 1 km/hr, find the speed of the steamer in still water and the distance between the ports.
It is given that the speed of the stream is 1 km/h.
Let the speed of the steamer in still water be x km/h.
∴Downstream speed = (x+1) km/h
Upstream speed = (x−1) km/h
The downstream and upstream distances are same; therefore, we have:
⇒9(x+1)=10(x−1)
⇒9x+9=10x−10
⇒x=19
∴Speed of the steamer in still water = 19 km/h.
Distance between the ports = 9(19+1)=180 km.