Question

Двигаясь по течению реки, расстояние в 72 км моторная лодка проходит за 2 ч, а плот за — 18 ч. Вычисли скорость моторной лодки при движении против течения реки.

Answer 1

72:18=4-скорости течения реки
72:2=36-скорость лодки по течению
36-4=32-скорость лодки
32-4=28-скорость лодки против течения

Answer 2

Calculation of the Speed of the Motorboat

To calculate the speed of the motorboat when moving against the current of the river, we need to use the formula:

Speed = Distance / Time

Given that the motorboat travels a distance of 72 km in 2 hours when moving with the current, we can calculate its speed as follows:

Speed with the current = 72 km / 2 hours = 36 km/h.

Now, let's calculate the speed of the motorboat when moving against the current. We know that the time it takes for the motorboat to cover the same distance of 72 km is 18 hours when moving against the current. Using the formula mentioned earlier, we can calculate the speed as follows:

Speed against the current = 72 km / 18 hours = 4 km/h.

Therefore, the speed of the motorboat when moving against the current of the river is 4 km/h.