Question

Лодка проплыла 15 км против течения реки.Собственная скорость лодки 7 км/ч,а скорость течения реки 2 км/ч . Сколько часов прплыла лодка решение и условие пожалуста!

Answer 1

1 .) 7 - 2 = 5 (км/ч) - скорость против течения
2.) 15 ÷ 5 = 3 (ч) - время (t)

Answer 2

Problem Statement:

Условие задачи: Лодка проплыла 15 км против течения реки. Собственная скорость лодки 7 км/ч, а скорость течения реки 2 км/ч. Сколько часов проплыла лодка?

Solution:

To solve this problem, we need to determine the time it took for the boat to travel 15 km against the current of the river. We can use the formula:

Time = Distance / Speed

In this case, the distance is 15 km and the speed of the boat is 7 km/h. However, we need to take into account that the boat is traveling against the current of the river, which has a speed of 2 km/h.

To find the effective speed of the boat against the current, we subtract the speed of the current from the speed of the boat:

Effective Speed = Boat Speed - Current Speed

In this case, the effective speed of the boat against the current is 7 km/h - 2 km/h = 5 km/h.

Now we can calculate the time it took for the boat to travel 15 km against the current using the formula:

Time = Distance / Effective Speed

Substituting the values, we get:

Time = 15 km / 5 km/h = 3 hours

Therefore, the boat took 3 hours to travel 15 km against the current of the river.

Answer:

The boat took 3 hours to travel 15 km against the current of the river.