Arjun can row at 11 km/hr in still water. The river flows at 3 km/hr. How far can he row up the river in 2 hours 15 minutes?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → 18 km
Up the river the current works against Arjun, so its speed is taken away; the time must be written in hours before it is multiplied by a speed in km/hr.
Upstream speed \(=11-3=8\) km/hr
Time \(\displaystyle =2\text{ hr }15\text{ min}=2+\frac{15}{60}=2.25\) hr
Distance \(=8\times2.25=18\) km