Question

Из одного села одновременно в противоположных направлениях выехал велосепидист и вышел пешеход. Скорость пешехода 70 м/мин, велосепидиста-в 3 раза больше. Через какое время расстояние между ними будет 840 м?

Answer 1

70 * 3 = 210   м/мин    скорость велосипедиста
70 + 210 = 280   м/мин    скорость удаления  (на сколько м они будут удаляться друг от друга за 1 минуту)
840 / 280 = 3   мин

Answer 2

Problem Analysis

We are given that a cyclist and a pedestrian start simultaneously from a village in opposite directions. The pedestrian's speed is 70 m/min, and the cyclist's speed is 3 times greater. We need to find the time it takes for the distance between them to reach 840 meters.

Solution

Let's denote the speed of the cyclist as v (in m/min). Since the cyclist's speed is 3 times greater than the pedestrian's speed, we have:

v = 3 * 70 = 210 m/min.

Let's denote the time it takes for the distance between them to reach 840 meters as t (in minutes).

During this time, the pedestrian will cover a distance of 70t meters, and the cyclist will cover a distance of 210t meters.

The sum of these distances should be equal to 840 meters:

70t + 210t = 840.

Simplifying the equation:

280t = 840.

Dividing both sides by 280:

t = 840 / 280 = 3.

Therefore, it will take 3 minutes for the distance between the cyclist and the pedestrian to reach 840 meters.

Answer

The distance between the cyclist and the pedestrian will be 840 meters after 3 minutes.

References

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