Question

1)Из села на железнодорожную станцию велосипедист ехал со скоростью 12км\ч.Возвращался он со скоростью 15км\ч и затратил на обратный путь на полчаса меньше.Сколько километров от села до станции? Нужно таблицу составить

Answer 1

Х- расстояние от села до станции . По условию задачи имеем  :
х/12 - х/15 = 1/2
15х - 12х = 90
3х = 90
х = 90 / 3
х = 30 км

Answer 2

Problem Analysis

We are given that a cyclist traveled from a village to a railway station at a speed of 12 km/h and returned at a speed of 15 km/h. The return trip took half an hour less than the initial trip. We need to find the distance between the village and the railway station.

Solution

Let's assume the distance between the village and the railway station is d kilometers.

We can use the formula time = distance / speed to calculate the time taken for each trip.

For the initial trip: - Time = distance / speed = d / 12

For the return trip: - Time = distance / speed = d / 15

According to the problem, the return trip took half an hour less than the initial trip. So we can write the equation:

(d / 12) - (d / 15) = 1/2

To solve this equation, we can multiply both sides by the least common multiple (LCM) of 12 and 15, which is 60:

60 * (d / 12) - 60 * (d / 15) = 60 * (1/2)

Simplifying the equation:

5d - 4d = 30

d = 30

Therefore, the distance between the village and the railway station is 30 kilometers.