Question

«Нз двух городов, находящuxся на расстоянии 520 км, одновременно выехали навстречу друг другу два поезда, которые встретились через 4 часа. Первый поезд ехал со скоростью 60 км/ч. С какой скоростью шел второй поезд?»

Answer 1

1. 60*4=240км проехал за 4 часа. 2. 520-240= 280км расстояние 2 поезд проехал за 4 часа. 3. 280:4 70км. Ехал с такой скоростью 2 поезд.

Answer 2

Problem Analysis

We are given that two trains start simultaneously from two cities that are 520 km apart and meet after 4 hours. The first train is traveling at a speed of 60 km/h. We need to find the speed of the second train.

Solution

To find the speed of the second train, we can use the formula: distance = speed × time.

Let's assume the speed of the second train is x km/h.

The first train travels for 4 hours at a speed of 60 km/h, so the distance it covers is: distance = speed × time = 60 km/h × 4 h = 240 km.

The second train also travels for 4 hours, but we don't know its speed. So, the distance it covers is: distance = speed × time = x km/h × 4 h = 4x km.

Since the two trains meet after 4 hours, the sum of the distances covered by both trains should be equal to the total distance between the cities, which is 520 km.

Therefore, we can write the equation: 240 km + 4x km = 520 km.

Simplifying the equation, we have: 4x km = 520 km - 240 km, 4x km = 280 km.

Dividing both sides of the equation by 4, we get: x km = 280 km / 4, x km = 70 km/h.

Therefore, the speed of the second train is 70 km/h.

Answer

The second train is traveling at a speed of 70 km/h.