Two cities, A and B, are located at a distance of 300 km from each other. Two cyclists leave these cities at the same

Two cities, A and B, are located at a distance of 300 km from each other. Two cyclists leave these cities at the same time to meet each other and race without stopping at a speed of 50 km / h. But together with the first cyclist, a fly flies out from city A, flying 100 km / h per hour. The fly is ahead of the first cyclist, flies towards the second, who left B. Having met him, she immediately turns back to the cyclist A. Having met him, she again flies back towards the cyclist B, and so she continued her flights back and forth until the cyclists came together. Then she calmed down and sat down on a hat for one of the cyclists. How many kilometers did the fly fly?

1. In order to determine the distance that the fly flew, it is necessary to multiply the speed of its movement by the time during which it was in flight.

2. The speed of the fly is known: according to the condition of the problem, it is equal to 100 km / h.

3. The time during which the fly flew is equal to the time elapsed before the meeting of the cyclists. Therefore, we need to determine the time from the start of the movement of cyclists to their meeting.

4. Since the cyclists were driving towards each other, the speed of their approach is equal to the sum of their speeds. That is, 50 km / h + 50 km / h = 100 km / h.

5. The cyclists met when they rode together all the way between cities A and B. That is, 300 km / 100 km / h = 3 hours.

6. That is, the fly flew for three hours. During this time she flew
3 h * 100 km / h = 300 km.

Answer: the fly flew 300 km.