Question

A motor boat travels 60 miles down a river in 3 hours but takes 5 hours to return upstream. Find the rate of the boat in still water and the rate of the current.

Answer 1

Explanation:

Given that,

A motor boat travels 60 miles down a river in 3 hours but takes 5 hours to return upstream,

We know that,

Speed = distance/time

The rate while moving downstream
`=(60)/(3)=20\ mph`

The rate while moving upstream
`=(60)/(5)=12\ mph`

The rate of the boat in still water is the average of these:

`v_s=(20+12)/(2)=16\ mph`

The rate of the current is the difference between the boat speed and actual speed = 16 mph - 12 mph = 4 mph

Hence, this is the required solution.