Answer:
40 km/h
Step-by-step explanation:
Let the speed of motorboat in still water = x km/h
Speed of current = 8 km/h
When moving with the current, the relative speed is = (x + 8) km/h
When moving against the current, the relative speed = (x - 8) km/h
Travelling against the current will take longer. So, it took 3 hours to travel against the current and 2 hours to travel in the direction of the current.
The distance traveled in each case remains the same.
Since, Distance = Speed x Time, we can write:
Distance traveled with current = Distance traveled against current
2(x + 8) = 3(x - 8)
2x + 16 = 3x - 24
16 + 24 = 3x - 2x
x = 40 km/h
Thus, the speed of motorboat in still water will be 40 km/h
