Question

Из двух городов расстояние между которыми 840 км , выехали два поезда на встречу друг другу. скорость первого 70 км /ч, а второго 80 км/ч. какое расстояние будет между ними через 2часа 30минут. помогите, пожалуйста!

Answer 1

2часа 30минут = 2.5
Первый проедет: 70 * 2.5 = 175 км
Второй проедет: 80 * 2.5 = 200 км
Расстояние будет между ними через 2часа 30минут: 840 - (175 + 200) = 465 км

Answer 2

Problem Analysis

We have two trains traveling towards each other from two cities that are 840 km apart. The first train has a speed of 70 km/h, and the second train has a speed of 80 km/h. We need to find the distance between them after 2 hours and 30 minutes.

Solution

To find the distance between the two trains after 2 hours and 30 minutes, we can calculate the total distance covered by both trains and subtract it from the initial distance of 840 km.

Let's calculate the distance covered by each train in 2 hours and 30 minutes.

The first train travels at a speed of 70 km/h. In 2 hours and 30 minutes, it covers a distance of: 2 hours and 30 minutes = 2.5 hours Distance covered by the first train = speed * time = 70 km/h * 2.5 hours = 175 km.

The second train travels at a speed of 80 km/h. In 2 hours and 30 minutes, it covers a distance of: Distance covered by the second train = speed * time = 80 km/h * 2.5 hours = 200 km.

Now, let's calculate the total distance covered by both trains: Total distance covered = distance covered by the first train + distance covered by the second train = 175 km + 200 km = 375 km.

Finally, let's find the distance between the two trains after 2 hours and 30 minutes: Distance between the two trains = initial distance - total distance covered = 840 km - 375 km = 465 km.

Answer: The distance between the two trains after 2 hours and 30 minutes will be 465 km.

Conclusion

In this problem, we calculated the distance between two trains traveling towards each other after a given time. We found that the distance between them after 2 hours and 30 minutes is 465 km.