Question

Помогите пожалуйста:От Пристани где скорость течения Москвы реки равна 4 км,одновременно отплывают плот и катер.Плот отплывает по течению реки катер против течения реки со скоростью 16 км.На каком расстоянии друг от друга плот и катер окажутся через 2 часа движения? Пожалуйста скажите как будет это задача действиями,а потом выражением!Я вас очень прошу помочь мне!вы-Люди с большим опытом!:( помогите пожалуйста!

Answer 1

4 + 16 = 20 км\час - скорость отдаления
20 * 2 = 40 км - расстояние, на котором окажутся плот и катер через 2 часа

Answer 2

Problem Analysis

In this problem, we are given that the speed of the current in the Moscow River is 4 km/h. A raft and a motorboat start moving simultaneously. The raft moves with the current, while the motorboat moves against the current at a speed of 16 km/h. We need to find the distance between the raft and the motorboat after 2 hours of movement.

Solution

To solve this problem, we can use the formula: distance = speed × time.

Let's calculate the distance traveled by the raft and the motorboat separately after 2 hours.

The speed of the current is given as 4 km/h. Since the raft moves with the current, its effective speed will be the sum of the speed of the current and its own speed. Therefore, the speed of the raft is 4 km/h.

Using the formula, the distance traveled by the raft after 2 hours is: distance_raft = speed_raft × time = 4 km/h × 2 h = 8 km.

On the other hand, the motorboat moves against the current, so its effective speed will be the difference between its own speed and the speed of the current. Therefore, the speed of the motorboat is 16 km/h - 4 km/h = 12 km/h.

Using the formula, the distance traveled by the motorboat after 2 hours is: distance_motorboat = speed_motorboat × time = 12 km/h × 2 h = 24 km.

Now, let's find the distance between the raft and the motorboat after 2 hours. Since they are moving in opposite directions, we can subtract the distance traveled by the raft from the distance traveled by the motorboat: distance_between = distance_motorboat - distance_raft = 24 km - 8 km = 16 km.

Therefore, after 2 hours of movement, the raft and the motorboat will be 16 km apart.

Expression

The distance between the raft and the motorboat after 2 hours can be expressed as: distance_between = (speed_motorboat - speed_raft) × time = (16 km/h - 4 km/h) × 2 h = 12 km/h × 2 h = 24 km - 8 km = 16 km.

So, the distance between the raft and the motorboat after 2 hours is 16 km.