Question

Два автомобиля выехали одновременно навстречу друг другу из двух городов,расстояние между которыми 750 км. Скорость первого автомобиля 64 км/ч. Через 2 часа после выезда автомобилей расстояние между ними уменьшилось до 450 км. с какой скоростью ехал второй автомобиль?

Answer 1

1) 64 * 2 = 128 (км) - проехал первый за 2 часа
2) 750 - 450 = 300 (км) - проехали оба за 2 часа
3) 300 - 128 = 172 (км) - проехал второй за 2 часа
4) 172 : 2 = 86 (км/ч) - скорость второго.

Answer 2

Problem Analysis

We are given that two cars start from two different cities and travel towards each other. The distance between the cities is 750 km. The first car has a speed of 64 km/h. After 2 hours, the distance between the cars reduces to 450 km. We need to find the speed of the second car.

Solution

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

The first car travels for 2 hours at a speed of 64 km/h. Therefore, the distance covered by the first car in 2 hours is 2 * 64 = 128 km.

After 2 hours, the distance between the cars reduces to 450 km. This means that the first car has covered 450 km - 128 km = 322 km.

Since the two cars are traveling towards each other, the sum of the distances covered by both cars should be equal to the total distance between the cities.

So, the distance covered by the second car is 750 km - 322 km = 428 km.

We can now set up the equation:

Distance = Speed * Time

For the first car: 128 km = 64 km/h * 2 h

For the second car: 428 km = x km/h * 2 h

Simplifying the equations, we get: 64 * 2 = 128 2x = 428

Solving for x, we find: x = 428 / 2 = 214 km/h

Therefore, the speed of the second car is 214 km/h.

Answer

The second car was traveling at a speed of 214 km/h.