A cargo boat moves at 17 km/hr in still water. The river flows at 3 km/hr. How long will the boat take to travel 60 km downstream?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → 3 hours
Going downstream, the river carries the boat along, so the river’s speed is added to the boat’s speed.
Downstream speed \(=17+3=20\) km/hr
Time \(\displaystyle =\frac{60}{20}=3\) hours