Question

Со станции одновременно в противоположных направлениях вышли две электрички. Скорость первой электрички 70 км в ч, скорость второй 90 км в ч. Какое расстояние будет между электричками через 5 часов? Нужно составить обратную задачу

Answer 1

1) 70+90=160(км/ч) - скорость удаления
2) 160×5=800(км) - расстояние между ними через 5 часов
Ответ: 800 км.

Answer 2

Problem Analysis

We are given that two trains start simultaneously from a station in opposite directions. The first train has a speed of 70 km/h, and the second train has a speed of 90 km/h. We need to find the distance between the trains after 5 hours.

Solution

To solve this problem, we can use the formula: distance = speed × time.

Let's calculate the distance traveled by each train after 5 hours.

For the first train: - Speed = 70 km/h - Time = 5 hours - Distance = 70 km/h × 5 hours = 350 km

For the second train: - Speed = 90 km/h - Time = 5 hours - Distance = 90 km/h × 5 hours = 450 km

Now, we need to find the total distance between the two trains. Since they are moving in opposite directions, we can add the distances traveled by each train.

Total distance = Distance of first train + Distance of second train Total distance = 350 km + 450 km = 800 km

Therefore, the distance between the two trains after 5 hours is 800 km.

Answer

The distance between the two trains after 5 hours is 800 km.