Question

С одной станции в противоположных направлениях вышли два поезда - пассажирский и товарный. Скорость товарного поезда 60 км/ч, а пассажирского - 90 км/ч. Через сколько времени расстояние между ними будет равно 450 км?

Answer 1

Через 3 часа
90+60=150 км/ч-скорость сблежения
450:150=3 часа

Answer 2

Problem Analysis

We have two trains, a passenger train and a freight train, both starting from the same station in opposite directions. The freight train has a speed of 60 km/h, while the passenger train has a speed of 90 km/h. We need to find out how much time it will take for the distance between them to be 450 km.

Solution

To find the time it takes for the distance between the two trains to be 450 km, we can use the formula:

Time = Distance / Relative Speed

The relative speed is the difference in speed between the two trains. In this case, the relative speed is the sum of the speeds of the two trains, since they are moving in opposite directions.

Let's calculate the time it takes for the distance between the two trains to be 450 km.

Calculation

The relative speed of the two trains is:

Relative Speed = Speed of Passenger Train + Speed of Freight Train

Substituting the given values:

Relative Speed = 90 km/h + 60 km/h = 150 km/h

Now, we can calculate the time it takes for the distance between the two trains to be 450 km:

Time = Distance / Relative Speed

Substituting the given distance:

Time = 450 km / 150 km/h = 3 hours

Therefore, it will take 3 hours for the distance between the two trains to be 450 km.

Answer

It will take 3 hours for the distance between the passenger train and the freight train to be 450 km.