Question

A sailor goes 8 km downstream in 40 minutes and returns in 1 hours. Determine the speed of the sailor in still water and the speed of the current.

Answer 1

Let the speed of the sailor in still water be x km/hr and the speed of the current be y km/hr

Speed upstream

Speed downstream

Now, Time taken to cover 8km down stream =

Time taken to cover 8km upstream=

But, time taken to cover 8 km downstream in 40 minutes or that is

Dividing both sides by common factor 2 we get

Time taken to cover 8km upstream in1hour

...(ii)

By solving these equation and we get

Substitute in equationwe get

Hence, the speed of sailor is

The speed of current is