Question

Из пункта А в пункт В выехал велосипедист со скоростью 12км/ч. Через час навстречу ему из В в А выехал второй велосипедист со скорость 14км/ч и встретился с первым через полчаса после своего выезда. Чему равн расстояние от А до В? Успеет ли первый велосипедист преодолеть это расстояние за 2 ч?

Answer 1

12*1,5=18 км // проехал первый велосипедист до встречи, 
14*0,5=7 км // проехал второй до встречи, 
7+18=25 км // расстояние между городами

Answer 2

Problem Analysis

We are given that a cyclist travels from point A to point B at a speed of 12 km/h. After an hour, another cyclist travels from point B to point A at a speed of 14 km/h. They meet each other half an hour after the second cyclist starts. We need to find the distance from point A to point B and determine if the first cyclist can cover this distance in 2 hours.

Solution

Let's assume the distance from point A to point B is d km.

We know that the first cyclist travels at a speed of 12 km/h, so in 1 hour, the first cyclist covers a distance of 12 km.

The second cyclist travels at a speed of 14 km/h and meets the first cyclist half an hour after starting. This means the second cyclist travels for 0.5 hours before meeting the first cyclist. Therefore, the distance covered by the second cyclist is 14 km/h * 0.5 h = 7 km.

When the two cyclists meet, the total distance covered by both of them is equal to the distance between point A and point B. So we can write the equation:

12 km + 7 km = d km

Simplifying the equation, we find:

19 km = d km

Therefore, the distance from point A to point B is 19 km.

To determine if the first cyclist can cover this distance in 2 hours, we need to calculate the time it takes for the first cyclist to cover the distance. We can use the formula:

time = distance / speed

Substituting the values, we find:

time = 19 km / 12 km/h = 1.58 hours

Since the first cyclist takes 1.58 hours to cover the distance, which is less than 2 hours, the first cyclist can indeed cover the distance from point A to point B in 2 hours.

Answer

The distance from point A to point B is 19 km. The first cyclist can cover this distance in 1.58 hours.