The speed of the boat along the river is 24 km / h and against the current 20 km / h, find the boat’s own speed.

First, we find the speed of the river.

Let’s designate the speed of its flow as unknown x.

Let’s compose and solve the equation, knowing the speed of the boat upstream and downstream of the river:

24 km / h – x = 20 km / h + x.

Let’s transfer all values with unknowns to one side, and known values to the other.

– x – x = 20 – 24;

– 2x = – 4;

2x = 4;

x = 4: 2;

x = 2 km / h.

Let’s find the boat’s own speed, substituting the value x = 2:

24 – 2 = 20 + 2;

22 = 22 km / h.

Answer: The boat’s own speed is 22 km / h.