Question

Rahul can row a certain distance downstream in 6hr and return the same in 9hr. If the speed of rahul in still water is 12 kph , find the speed of the stream

Answer 1

Rahul the body here, travels the same distance(x) in both downstream(6hr) and upstream(9hr).

So, V*T for both must be constant equal to X.

So, downstream speed of Rahul is-

12km/hr (given) along with the supportive V speed of river,

(12+V) and time- 6hr

Upstream-

(12-V) and time- 9hr

Since, V*T is constant.

(12-V)*(9hr)=(12+V)*(6hr)

So, simply V here comes out as 2.4 km/hr as the river speed.