Question

Из двух городов, расстояние между которыми равно 750 км, на встречу друг другу одновременно выехали два автомобиля. Найдите скорость первого автомобиля, если скорость второго равна 80 км/ч и автомобили встретились через 5 часов после выезда.

Answer 1

750/5=150км/ч-скорость сближения
150-80=70км/ч-скорость первого авто

Answer 2

Problem Analysis

We are given that two cars start simultaneously from two cities that are 750 km apart. We are also given that the second car is traveling at a speed of 80 km/h and the cars meet after 5 hours. We need to find the speed of the first car.

Solution

Let's assume the speed of the first car is x km/h.

We can use the formula: distance = speed × time to find the distance traveled by each car.

The distance traveled by the first car is x × 5 km.

The distance traveled by the second car is 80 × 5 km.

Since the total distance between the two cities is 750 km, we can write the equation:

x × 5 + 80 × 5 = 750

Simplifying the equation:

5x + 400 = 750

5x = 750 - 400

5x = 350

x = 350 / 5

x = 70

Therefore, the speed of the first car is 70 km/h.

Answer

The speed of the first car is 70 km/h.