Question

Помогите решить задачу.Из двух городов,расстояние между которыми 636км.,навстречу друг другу в разное время вышли 2 товарных поезда.Скорость первого поезда 40км/ч,второго-на 6км/ч больше.Пройдя 276км.,второй поезд встретился с первым.Какой поезд вышел раньше и на сколько?ПОМОГИТЕ ПРОШУ!

Answer 1

2 й вышел раньше на 3 часа

Answer 2

Problem Analysis

We are given that two freight trains start from two different cities and are traveling towards each other. The distance between the cities is 636 km. The first train has a speed of 40 km/h, while the second train has a speed that is 6 km/h faster than the first train. After traveling 276 km, the second train meets the first train. We need to determine which train started earlier and by how much time.

Solution

Let's assume that the first train started x hours earlier than the second train.

The distance covered by the first train in x hours is given by: Distance1 = Speed1 * Time1

The distance covered by the second train in (x - 276) hours is given by: Distance2 = Speed2 * Time2

Since the total distance between the two cities is 636 km, we can write the equation: Distance1 + Distance2 = 636

Substituting the values for Distance1 and Distance2, we get: (Speed1 * Time1) + (Speed2 * Time2) = 636

We also know that the second train meets the first train after traveling 276 km. So, we can write another equation: Distance2 = 276

Substituting the value for Distance2, we get: Speed2 * Time2 = 276

Since we are given that the speed of the second train is 6 km/h faster than the speed of the first train, we can write: Speed2 = Speed1 + 6

Now, we have two equations: (Speed1 * Time1) + (Speed2 * Time2) = 636 Speed2 * Time2 = 276

We can solve these equations to find the values of Time1 and Time2, which will help us determine which train started earlier and by how much time.

Let's solve the equations:

From the equation Speed2 * Time2 = 276, we can express Time2 in terms of Speed2: Time2 = 276 / Speed2

Substituting the value of Speed2 in terms of Speed1: Time2 = 276 / (Speed1 + 6)

Now, we can substitute the value of Time2 in the equation (Speed1 * Time1) + (Speed2 * Time2) = 636: (Speed1 * Time1) + (Speed2 * (276 / (Speed1 + 6))) = 636

Simplifying the equation: Speed1 * Time1 + (276 * Speed2) / (Speed1 + 6) = 636

Now, we can substitute the value of Speed2 in terms of Speed1: Speed1 * Time1 + (276 * (Speed1 + 6)) / (Speed1 + 6) = 636

Simplifying further: Speed1 * Time1 + 276 = 636

Subtracting 276 from both sides of the equation: Speed1 * Time1 = 360

Now, we can express Time1 in terms of Speed1: Time1 = 360 / Speed1

We know that the speed of the first train is 40 km/h, so substituting the value of Speed1: Time1 = 360 / 40 = 9 hours

Therefore, the first train started 9 hours earlier than the second train.

To summarize: - The first train started 9 hours earlier than the second train. - The second train started later.

Please let me know if you need any further assistance!