Question

Два пешехода вышли одновременно навстречу друг другу.Скорость одного из них 5.1км/ч и она больше скорости другого на 0.7км/ч.Через 0.8ч они встретились.Какое расстояние было между ними в начале пути?

Answer 1

5.1*0.8+(5.1-0.7)*0,8=4,08+3,52=7,6км
Ответ:7,6км

Answer 2

Problem Analysis

We have two pedestrians walking towards each other. The speed of one pedestrian is 5.1 km/h, which is 0.7 km/h faster than the other pedestrian. After 0.8 hours, they meet. We need to find the initial distance between them.

Solution

Let's assume the speed of the slower pedestrian is x km/h. Since the speed of the faster pedestrian is 0.7 km/h faster, their speed would be x + 0.7 km/h.

We can use the formula distance = speed × time to calculate the distance traveled by each pedestrian.

The slower pedestrian travels a distance of x × 0.8 km in 0.8 hours.

The faster pedestrian travels a distance of (x + 0.7) × 0.8 km in 0.8 hours.

Since they meet, the sum of their distances traveled should be equal to the initial distance between them.

Therefore, we can set up the equation:

x × 0.8 + (x + 0.7) × 0.8 = initial distance

Simplifying the equation:

0.8x + 0.8(x + 0.7) = initial distance

Solving for x:

1.6x + 0.56 = initial distance

Now, we can substitute the given values into the equation and solve for the initial distance.

1.6(5.1) + 0.56 = initial distance

8.16 + 0.56 = initial distance

8.72 = initial distance

Therefore, the initial distance between the two pedestrians was 8.72 kilometers.

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