The motor ship traveled for 3 hours along the lake at a speed of 23 km / h, and then for 4 hours along the river.

The motor ship traveled for 3 hours along the lake at a speed of 23 km / h, and then for 4 hours along the river. How many kilometers did the motor ship travel in these 7 hours if it walked along the arm 3 km / h faster than along the lake.

First, let’s find the path that the motor ship took along the lake:
23 * 3 = 69 km.
The ship went along the river at a speed:
23 + 3 = 26 km / h.
In 4 hours the ship passed along the river:
4 * 26 = 104 km.
For 7 hours the ship passed along the lake and river:
69 + 104 = 173 km.
Answer: the motor ship covered only 173 km in 7 hours.