A pedestrian left point a to point b at a speed of 5 km / h. At the same time, a cyclist left A to B at a speed of 10 km / h

A pedestrian left point a to point b at a speed of 5 km / h. At the same time, a cyclist left A to B at a speed of 10 km / h in the same direction. The cyclist reached B, turned back and rode at the same speed. How many hours after the start of the movement will they meet? If the distance from A to B is 30 km …

1. We calculate how many hours the cyclist reached point B:

30: 10 = 3 hours.

2. Accepted for x time after the departure of the cyclist from point B, after which they will meet.

3. The traveler walked to the meeting point (x + 3) hours.

4. The cyclist traveled from point B to the meeting point 10x kilometers, the traveler walked from point A to the meeting point 5 (x +3) kilometers.

5. Taking into account that the total length of the path of the traveler and the cyclist is 30 kilometers, we make the equation:

5 (x + 3) + 10x = 30;

5x + 15 + 10x = 30;

15x = 15;

x = 1 hour.

6. The traveler will approach, and the cyclist will drive up to the meeting point in 4 hours (1 hour + 3 hours = 4 hours) after their departure from point A.

Answer: the traveler will come up, and the cyclist will drive up to the meeting point 4 hours after they leave from point A.