Question

Решите задачу с помощью уравнения собственная скорость теплохода в 9 раз больше чем скорость течения реки по течению Теплоход проходит 45 км за 1 час 15 минут Найдите скорость теплохода против течения​

Answer 1

1) 45÷1,25=36 (км/ч)-скорость теплохода по течению

x (км/ч) -скорость течения

9x (км/ч)-собственная скорость теплохода

x+9x=36

10x=36

x=3,6 (км/ч)-скорость течения

2) 9×3,6=32,4 (км/ч)- собственная скорость теплохода

3) 32,4-3,6=28,8 (км/ч)-скорость теплохода против течения

Answer 2

Problem Analysis

To solve this problem, we need to find the speed of the ship against the current. We are given that the ship's speed is 9 times greater than the speed of the river's current. Additionally, we know that the ship travels 45 km in 1 hour and 15 minutes.

Solution

Let's assume the speed of the river's current is x km/h. According to the problem, the speed of the ship is 9 times greater than the speed of the river's current. Therefore, the speed of the ship can be expressed as 9x km/h.

We are given that the ship travels 45 km in 1 hour and 15 minutes, which is equivalent to 1.25 hours. We can use the formula distance = speed × time to find the speed of the ship against the current.

The equation can be written as: 45 = (9x - x) × 1.25

Simplifying the equation: 45 = 8x × 1.25

Now, we can solve for x to find the speed of the river's current.

Calculation

Let's calculate the speed of the river's current.

45 = 8x × 1.25

Dividing both sides of the equation by 1.25: 36 = 8x

Dividing both sides of the equation by 8: x = 4.5

Therefore, the speed of the river's current is 4.5 km/h.

Since the speed of the ship is 9 times greater than the speed of the river's current, we can calculate the speed of the ship against the current.

Speed of the ship = 9 × speed of the river's current Speed of the ship = 9 × 4.5 Speed of the ship = 40.5 km/h

Answer

The speed of the ship against the current is 40.5 km/h.

Please let me know if you need any further assistance!