Question

Из двух городов навстречу друг другу одновременно отправились два поезда .Скорость одного 60км/ч,другой за 1 час проходит на 20 км больше .Через 3 часа 30 минут поезда встретились. Найди расстояние между городами.

Answer 1

60+20=80км/ч скорость2 поезда
3,5*60=210км до всречи прошел 1 поезд
3,5*80=280км до встреч 2 поезд
280+210=490км растояние между городами

Answer 2

Problem Analysis

We are given that two trains start simultaneously from two cities and meet after 3 hours and 30 minutes. The speed of one train is 60 km/h, and the other train covers 20 km more in 1 hour. We need to find the distance between the two cities.

Solution

Let's assume that the distance between the two cities is d km.

We know that the speed of the first train is 60 km/h. Therefore, in 3 hours and 30 minutes (or 3.5 hours), the first train will cover a distance of 60 * 3.5 = 210 km.

Now, let's find the speed of the second train. We are given that the second train covers 20 km more than the first train in 1 hour. So, the speed of the second train is 60 + 20 = 80 km/h.

Since both trains are traveling towards each other, their combined speed is 60 + 80 = 140 km/h.

We know that the total time taken for the two trains to meet is 3 hours and 30 minutes, which is 3.5 hours.

Using the formula distance = speed * time, we can calculate the distance between the two cities:

d = (speed of the first train + speed of the second train) * time

Substituting the values, we get:

d = 140 * 3.5 = 490 km

Therefore, the distance between the two cities is 490 km.

Answer

The distance between the two cities is 490 km.