Step-by-step 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[tex]=\dfrac{60}{3}=20\ mph[/tex]
The rate while moving upstream [tex]=\dfrac{60}{5}=12\ mph[/tex]
The rate of the boat in still water is the average of these:
[tex]v_s=\dfrac{20+12}{2}=16\ mph[/tex]
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.