The boat’s own speed is 10 times greater than the speed of the river flow in 5 hours

The boat’s own speed is 10 times greater than the speed of the river flow in 5 hours, the boat has covered 90 km upstream Find your own speed and the speed of the river.

We take the speed of the river flow as x km / h;

Then the boat’s own speed is 10 km / h;

The speed of the boat against the current is (10x – x) km / h;

We compose and solve the equation.

(10x – x) * 5 = 90;

50x – 5x = 90;

45x = 90;

x = 2;

The speed of the river is 2 km / h.

The boat’s own speed is 2 * 10 = 20 km / h.