A boat moves at 6 m/s in still water, and the stream flows at 1 m/s. What is the upstream speed of the boat in km/hr?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → 18 km/hr
Upstream the stream’s speed is taken away; then 1 m/s \(\displaystyle =\frac{18}{5}\) km/hr changes the unit.
Upstream speed \(=6-1=5\) m/s
In km/hr: \(\displaystyle 5\times\frac{18}{5}=18\) km/hr