Question

Из двух городов между которыми расстояние 900км,выехали навстречу друг другу вышли 2поезда.скорость 1-го 45км/ч,а второго 55км/ч. через сколько часов поезда встретятся?

Answer 1

1)45+55=100км/ч - скорость сближения
2) 900:100=9ч 
Ответ : через 9ч

Answer 2

Problem Analysis

We have two trains traveling towards each other from two different cities. The distance between the cities is 900 km. The first train is traveling at a speed of 45 km/h, and the second train is traveling at a speed of 55 km/h. 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 / Relative Speed

The relative speed is the sum of the speeds of the two trains. Let's calculate the time it takes for the trains to meet.

Calculation

The relative speed of the two trains is 45 km/h + 55 km/h = 100 km/h.

Using the formula, we can calculate the time it takes for the trains to meet:

Time = 900 km / 100 km/h

Simplifying the equation, we get:

Time = 9 hours

Therefore, the trains will meet after 9 hours.

Answer

The trains will meet after 9 hours.

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