Question

Два хлопчики з однаковою швидкістю (80м/хв) вийшли назустріч один одному. Відстань між ними 960м. З одним хлопчиком був собака, який біг у 4 рази швидше , ніж ішов хлопчик. Собака бігав від одного хлопчика до іншого. Скільки метрів пробіг собака, поки хлопчики йшли назустріч один одному?

Answer 1

Мальчики шли навстречу друг другу со скоростью 80 м/хв. Их общая скорость была 80 * 2 = 160 м/хв. Они встретились через 960 : 160 = 6 хвилин. Скорость собаки была 4 * 80 = 320 м/хв. За 6 хв. она пробежала 6 * 320 = 1920 метров.

Удачи!

Answer 2

Problem Analysis

We have two boys walking towards each other at the same speed of 80 m/min. The distance between them is 960 m. There is a dog running between the boys, and it runs 4 times faster than the boys walk. We need to calculate how far the dog runs while the boys are walking towards each other.

Solution

To solve this problem, we can use the concept of relative speed. The relative speed between the boys is the sum of their individual speeds. Since they are walking towards each other, their relative speed is 80 m/min + 80 m/min = 160 m/min.

Now, let's calculate the time it takes for the boys to meet each other. We can use the formula:

Time = Distance / Speed

The distance between the boys is 960 m, and their relative speed is 160 m/min. Substituting these values into the formula, we get:

Time = 960 m / 160 m/min = 6 min

So, it takes 6 minutes for the boys to meet each other.

During this time, the dog is running between the boys. The dog's speed is 4 times faster than the boys' walking speed, which means the dog's speed is 4 * 80 m/min = 320 m/min.

To calculate the distance the dog runs, we can use the formula:

Distance = Speed * Time

Substituting the values, we get:

Distance = 320 m/min * 6 min = 1920 m

Therefore, the dog runs a distance of 1920 meters while the boys are walking towards each other.

Answer

The dog runs a distance of 1920 meters while the boys are walking towards each other.