The motor ship covered the distance between the quays at a speed of 40 km / h in 4.5 hours.

The motor ship covered the distance between the quays at a speed of 40 km / h in 4.5 hours. A motor ship must go at what speed to cover this distance in 3.6 hours.

Let us determine the distance between the quays if it is known that the ship covered it in 4.5 hours, moving at a speed of 40 km / h.
4.5 × 40 = 180 kilometers.
If a motor ship needs to cover this distance in 3.6 hours, then the speed with which it must move will be:
180: 3.6 = 50 km / h.
Answer: the speed of the ship will be 50 kilometers per hour.