The boat sailed 92 km along the river. the speed of the river is 3 km / h

The boat sailed 92 km along the river. the speed of the river is 3 km / h, and the boat’s own speed is 20 km / h. how many hours the boat sailed.

Since the speed of the river is 3 km / h, and the boat’s own speed is 20 km / h, the speed of the boat along the river is equal to the sum of the speed of the boat and the speed of the river:

1) 20 + 3 = 23 km / h;

The boat sailed only 92 km at a speed of 23 km / h. Thus, to calculate the time spent on movement
you need to divide the distance that the boat has covered by its speed downstream:

2) 92:23 = 4 hours.

Answer: the boat sailed for 4 hours.