Question

Из двух городов, расстояние между которыми 1200 км, вышли одновременно навстречу друг другу два поезда. Один из них проходит это расстояние за 20 ч, другой-за 30 ч. Через сколько часов поезда встретятся?

Answer 1

1200:20=60 км/год -1-й поїзд.   1200:30=40 км/год-2-й поїзд.                        1200:(60+40)=12 год.

Answer 2

1) Делим растояние на часы: 1200км: 20 ч= 60 км/ч -это скорость первого поезда; 2) 1200: 30 ч=40 км/ч -скорость второго поезда; 3) находим общую скорость: 60 + 40 = 100 км/ч 4) разделим растояние на общую скорость и получим время: 1200 : 100=12 ч ответ: Поезда встретятся через 12 часов.

Answer 3

Problem Analysis

We have two trains traveling towards each other from two different cities. The distance between the cities is 1200 km. One train takes 20 hours to cover this distance, while the other train takes 30 hours. We need to determine how many hours it will take for the trains to meet.

Solution

To find the time it takes for the trains to meet, we can use the formula:

Time = Distance / Speed

Let's calculate the speeds of the trains first.

The speed of the first train is given by:

Speed of first train = Distance / Time = 1200 km / 20 hours = 60 km/h.

The speed of the second train is given by:

Speed of second train = Distance / Time = 1200 km / 30 hours = 40 km/h.

Now, we can calculate the time it takes for the trains to meet. Since they are traveling towards each other, their speeds will add up:

Total speed = Speed of first train + Speed of second train = 60 km/h + 40 km/h = 100 km/h.

Finally, we can find the time it takes for the trains to meet using the formula:

Time = Distance / Speed = 1200 km / 100 km/h = 12 hours.

Therefore, the trains will meet after 12 hours.

Answer

The trains will meet after 12 hours.