A boat and a motor ship set off from the two piers to meet each other at the same time. The boat’s own speed

A boat and a motor ship set off from the two piers to meet each other at the same time. The boat’s own speed was 10.8 km / h. The boat moved along the river, and the motor ship, 30.2 km / h, moved against the current. How many hours after the start of the movement. they will meet if the distance between the marinas is -205 km

Let the speed of the river flow x km / h.

The boat was moving with the current, so its speed was:

(10.8 + x) km / h.

The motor ship was moving against the flow of the river, which means its speed was:

(30.2 – x) km / h.

Let the boat and the ship meet at the clock.

Then the boat sailed:

(10.8 + x) * y = (10.8y + xy) km.

The motor ship sailed during this time:

(30.2 – x) * y = (30.2x – xy) km.

The distance between the marinas is 205 km, we will compose and solve the equation:

10.8x + xy + 30.2 x – xy = 205,

41x = 205,

x = 5 hours.

Answer: the boat and the ship will meet in 5 hours.