Question

Из пункта А в пункт В, расстояние между которыми равно 17 км, выехал велосипедист со скоростью 12 км/ч. Одновременно с ним из А в В вышел пешеход со скоростью 5 км/ч. Велосипедист дое-хал до пункта В, повернул обратно с той же скоростью. Через сколько часов после начала движения они встретятся? ПОМОГИТЕ

Answer 1

Нужно составить схему

велосипедист за 1 час проедет 12 км, а за 2 часа :
12* 2=24км
от пункта А до пункта В расстояние 17 км,значит:
24-17=7км- он окажется на обратном пути, т.е. из пункта В до А

пешеход за 1 час пройдёт 5 км /ч,а за 2 часа
5*2=10км

10+7=17км-расстояние от А до В,значит они встретятся через 2 часа .
ответ через 2 часа

Answer 2

Problem Analysis

We are given that a cyclist and a pedestrian start simultaneously from point A and point B, respectively, with a distance of 17 km between them. The cyclist travels at a speed of 12 km/h, while the pedestrian travels at a speed of 5 km/h. The cyclist reaches point B, turns back, and continues to travel at the same speed. We need to determine how many hours it will take for them to meet.

Solution

To solve this problem, we can use the concept of relative speed. The relative speed between the cyclist and the pedestrian is the sum of their individual speeds. In this case, the relative speed is 12 km/h + 5 km/h = 17 km/h.

Since the distance between point A and point B is 17 km, the time it takes for them to meet can be calculated by dividing the distance by the relative speed:

Time = Distance / Relative Speed

Substituting the values, we get:

Time = 17 km / 17 km/h = 1 hour

Therefore, the cyclist and the pedestrian will meet after 1 hour.

Answer

The cyclist and the pedestrian will meet after 1 hour.

Explanation

The cyclist and the pedestrian start simultaneously from point A and point B, respectively, with a distance of 17 km between them. The cyclist travels at a speed of 12 km/h, while the pedestrian travels at a speed of 5 km/h. Since the relative speed between them is 17 km/h, they will meet after 1 hour of traveling.