Question

Из двух поселков одновременно навстречу к друг другу вышли два пешехода. Расстояние между поселками 21км.Первый шел со скоростью 3км/ч, а второй- со скоростью 4км/ч. Через сколько часов они встретились

Answer 1

1) 3+4=7 км/час скорость сближения пешеходов                                                  2) 21:7=3 (через 3 часа пешеходы встретились)                                                  Ответ: Пешеходы встретились через 3 часа

Answer 2

Problem Analysis

We have two pedestrians walking towards each other from two different villages. The distance between the villages is 21 km. The first pedestrian is walking at a speed of 3 km/h, and the second pedestrian is walking at a speed of 4 km/h. We need to determine how many hours it will take for them to meet.

Solution

To solve this problem, we can use the formula: time = distance / speed.

Let's calculate the time it will take for the pedestrians to meet.

The first pedestrian is walking at a speed of 3 km/h. Let's calculate the time it will take for the first pedestrian to cover the distance between the villages.

Time taken by the first pedestrian = distance / speed = 21 km / 3 km/h = 7 hours. Similarly, the second pedestrian is walking at a speed of 4 km/h. Let's calculate the time it will take for the second pedestrian to cover the distance between the villages.

Time taken by the second pedestrian = distance / speed = 21 km / 4 km/h = 5.25 hours. Since they are walking towards each other, the total time taken for them to meet will be the sum of the times taken by each pedestrian.

Total time taken = time taken by the first pedestrian + time taken by the second pedestrian = 7 hours + 5.25 hours = 12.25 hours.

Therefore, it will take them approximately 12.25 hours to meet.

Answer

The two pedestrians will meet approximately after 12.25 hours.

References

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