Question

A boat travels with a speed of 17 km h in still water. If the speed of the stream is
7 km h-!, find: the time taken by the boat to go 72 km downstream.​

Answer 1

Given: Boat travels at a speed of 22 km/hr.

Speed of stream is 8 km/hr.

Speed of boat to go downstream =22+8=30 km/hr

Distance to go downstream =135 km

Hence, to calculate time taken:

Speed =

distance

time

Time = 135

30

$4\frac{1}{2}$

ans