Question

От пристани вверх по реке отошел катер, а через 2 ч после этого вниз по течению реки отошел второй катер. Собственная скорость каждого катера равна V км/ч, а скорость течения реки W км/ч. Запишите в виде выражения, каково будет расстояние между катерами через 3 ч после начала движения второго катера.

Answer 1

Расстояние от пристани первого катера будет равно
5*(V+W), а второго катера 3*(V+W)
расстояние между катерами будет равно
5*(V+W)- 3*(V+W)=2* (V+W)

Answer 2

Problem Analysis

We are given two boats that start their journey at a dock on a river. The first boat moves upstream, while the second boat moves downstream. The speed of each boat is given as V km/h, and the speed of the river's current is given as W km/h. We need to determine the distance between the two boats after 3 hours from the start of the second boat's movement.

Solution

To find the distance between the two boats after 3 hours, we need to calculate the distances traveled by each boat during this time.

Let's assume the distance traveled by the first boat (moving upstream) after 3 hours is D1, and the distance traveled by the second boat (moving downstream) after 3 hours is D2.

The formula to calculate the distance traveled is:

Distance = Speed × Time

For the first boat (moving upstream), the effective speed is the difference between the boat's speed and the speed of the river's current:

Effective Speed of the First Boat = V - W

Using this effective speed, we can calculate the distance traveled by the first boat after 3 hours:

D1 = (V - W) × 3

For the second boat (moving downstream), the effective speed is the sum of the boat's speed and the speed of the river's current:

Effective Speed of the Second Boat = V + W

Using this effective speed, we can calculate the distance traveled by the second boat after 3 hours:

D2 = (V + W) × 3

Finally, the distance between the two boats after 3 hours can be calculated as the difference between the distances traveled by the first and second boats:

Distance between the Boats = D2 - D1

Let's substitute the given values of V and W into the formulas and calculate the distance between the two boats after 3 hours.

Calculation

Given: - Speed of each boat (V) = V km/h - Speed of the river's current (W) = W km/h - Time = 3 hours

Using the formulas derived above, we can calculate the distance between the two boats after 3 hours:

D1 = (V - W) × 3

D2 = (V + W) × 3

Distance between the Boats = D2 - D1

Answer

The distance between the two boats after 3 hours from the start of the second boat's movement is (V + W) × 3 - (V - W) × 3 kilometers.

Please note that the specific values of V and W were not provided in the question, so the answer is expressed in terms of these variables.