Question

Из пункта A в пункт B вышел пешеход со скоростью 4,7 км/ч, а из пункта B в пункт A вышел второй пешеход со скоростью 5,2 км/ч. На расстоянии 14,1 км от пункта A пешеходы встретились. На сколько часов раньше вышел первый пешеход, если расстояние между пунктами равно 21,9 км?

Answer 1

Если пешеходы встретились на рассоянии 14,1 км, то один из них прошел 14,1 км, а другой 7,8 км т.к. 21,9 - 14,1 = 7,8
t1 = 14,1 / 4,7 = 3ч
t2 = 7,8 / 5,2 = 1,5ч
3 - 1,5 = 1,5ч => 1 пешеход вышел на 1,5ч раньше

Answer 2

Problem Analysis

We are given that two pedestrians start walking from point A to point B and from point B to point A, respectively. The first pedestrian walks at a speed of 4.7 km/h, while the second pedestrian walks at a speed of 5.2 km/h. The distance between point A and point B is 21.9 km. We need to determine how many hours earlier the first pedestrian started walking if they met at a point 14.1 km from point A.

Solution

Let's assume that the first pedestrian started walking x hours earlier than the second pedestrian. We can use the formula `distance = speed * time` to calculate the time taken by each pedestrian to reach the meeting point.

For the first pedestrian: - Distance = 14.1 km - Speed = 4.7 km/h - Time = 14.1 km / 4.7 km/h = 3 hours

For the second pedestrian: - Distance = 21.9 km - 14.1 km = 7.8 km (remaining distance to the meeting point) - Speed = 5.2 km/h - Time = 7.8 km / 5.2 km/h = 1.5 hours

Since the first pedestrian started walking x hours earlier, the total time taken by the first pedestrian is 3 hours + x hours. We can set up the following equation:

3 hours + x hours = 1.5 hours

Simplifying the equation, we get:

x = 1.5 hours - 3 hours = -1.5 hours

Since time cannot be negative, we can conclude that the first pedestrian did not start walking earlier. Therefore, the first pedestrian and the second pedestrian started walking at the same time.

Answer

The first pedestrian did not start walking earlier than the second pedestrian. They both started walking at the same time.