Question

Поезд проходит расстояние между городами за 8 часов. Если он увеличит скорость на 20 км/ ч, то пройдёт это расстояние за 6 ч. Найдите скорость поезда и расстояние между городами. Помогите!!!!

Answer 1

X км/ч - скорость поезда, а станет x+20. Тогда
8x=6(x+20)
8x=6x+120
8x-6x=120
2x=120
x=120:2
x=60 км/ч - была первоначальная
скорость поезда
60*8=480 км - расстояние между городами

Answer 2

Пусть за х км/ч-поезд проходит расстояние между городами за 8ч.
составим уравнение:
8x=6(x+20)
8х=6х+120
2х=120
х=60
2)
8*60=480(км)-расстояние между городами.
3)60+20=80(км/ч)-при увеличении скорости.
Ответ:460км,60км в часза 8 часов , 80 км/ч-при увеличении скорости.

Answer 3

Problem Analysis

We are given that a train travels a certain distance between two cities in 8 hours. If the train increases its speed by 20 km/h, it can cover the same distance in 6 hours. We need to find the speed of the train and the distance between the cities.

Solution

Let's assume the initial speed of the train is x km/h and the distance between the cities is d km.

According to the given information, we can set up the following equations:

Equation 1: The train covers the distance in 8 hours at the initial speed: d = x * 8.

Equation 2: The train covers the same distance in 6 hours at a speed increased by 20 km/h: d = (x + 20) * 6.

To solve this system of equations, we can substitute Equation 1 into Equation 2:

x * 8 = (x + 20) * 6.

Now, let's solve this equation to find the value of x.

Calculation

Expanding the equation:

8x = 6x + 120.

Simplifying:

2x = 120.

Dividing both sides by 2:

x = 60.

The initial speed of the train is 60 km/h.

Now, we can substitute this value back into Equation 1 to find the distance d:

d = 60 * 8.

Calculating:

d = 480.

The distance between the cities is 480 km.

Answer

The speed of the train is 60 km/h and the distance between the cities is 480 km.

Please let me know if I can help you with anything else.