Question

Решите задачу: Отношение собственной скорости катера к скорости течения реки равно 9:1. Собственная скорость катера на 18, 4 км/ч больше скорости течения. Какое расстояние проплывет катер за 2,5 часа против течения реки? помогите плиз срочно даю 50 баллов честно

Answer 1

Х - течение реки
9х - скорость катера
9х - х = 18,4
8х = 18,4
х = 2,3 - скорость течения.
2,3 * 9 = 20,7 - скорость катера.

20,7 - 2,3 = 18,4 - скорость катера против течения.
18,4 * 2,5 = 46 км - проплывёт катер против течения за 2,5 часа.

Answer 2

Problem Analysis

We are given that the ratio of the boat's own speed to the speed of the river current is 9:1. The boat's own speed is 18.4 km/h greater than the speed of the current. We need to find the distance the boat will travel against the current in 2.5 hours.

Solution

Let's assume the speed of the river current is x km/h.

According to the given information, the boat's own speed is 18.4 km/h greater than the speed of the current. So, the boat's speed is x + 18.4 km/h.

The ratio of the boat's own speed to the speed of the current is given as 9:1. Therefore, we can set up the following equation:

(x + 18.4) / x = 9 / 1

To solve this equation, we can cross-multiply:

(x + 18.4) * 1 = 9 * x

Simplifying the equation:

x + 18.4 = 9x

18.4 = 9x - x

18.4 = 8x

Dividing both sides by 8:

x = 18.4 / 8

x = 2.3

So, the speed of the river current is 2.3 km/h.

Now, we can calculate the boat's speed:

Boat's speed = x + 18.4 = 2.3 + 18.4 = 20.7 km/h

To find the distance the boat will travel against the current in 2.5 hours, we can use the formula:

Distance = Speed * Time

Distance = 20.7 km/h * 2.5 hours

Distance = 51.75 km

Therefore, the boat will travel a distance of 51.75 km against the current in 2.5 hours.

Answer

The boat will travel a distance of 51.75 km against the current in 2.5 hours.