The boat’s own speed is 5 times higher than the current speed.

The boat’s own speed is 5 times higher than the current speed. The boat goes downstream for 36 km in 3 hours. How many km will the boat sail upstream in 2 hours?

In order to solve this problem, it is necessary to draw up an equation.
Let x km / h be the speed of the river, then 5x km / h is the speed of the boat. Since we know that the boat, moving downstream for three hours, sailed 36 kilometers, we have the equation:
36 = (x + 5x) * 3;
(The equation is based on the distance formula, which equals the product of speed and time);
12 = x + 5x;
6x = 12;
x = 2 km / h – river flow speed;
Find the speed of the boat:
2 * 5 = 10 km / h;
Now let’s find out how far the boat will sail in 2 hours, moving against the current:
2 * (10 – 2) = 2 * 8 = 16 km;
Answer: 16 km.