Question

Расстояние между двумя пунктами 20км.первый поезд это расстояние пройдет за 50 мин быстрее, чем второй. Скорость первого поезда на 12км/ч больше чем скорость второго. Найдите скорость каждого поезда срочноо

Answer 1

50м -0,83ч ,20:0,83=24км.ч, 24-12=12,Скорость 1-го 24км.ч,2-го 12км.ч                                                                                                                                                            

Answer 2

Пусть скорость первого поезда - х, а второго - у.     50 мин=5/6 час.

x-y=12         x=y+12

20/y-20/x=5/6  |×6xy    

120x-120y=5xy

120*(y+12)-120y=5y*(y+12)

120y+1440-120y=5y²+60y

5y²+60y-1440=0  |÷5

y²+12y-288=0   D=1296    √D=36

y₁=12      y₂=-24  ∉    ⇒

x=12+12=24.

Ответ: скорость первого поезда 24 км/ч, скорость второго поезда 12 км/ч.

Answer 3

Problem Analysis

We are given that the distance between two points is 20 km. The first train covers this distance in 50 minutes less than the second train. The speed of the first train is 12 km/h greater than the speed of the second train. We need to find the speed of each train.

Solution

Let's assume the speed of the second train is x km/h. Then, the speed of the first train would be x + 12 km/h.

We can use the formula distance = speed × time to calculate the time taken by each train to cover the distance of 20 km.

For the first train: - Distance = 20 km - Speed = x + 12 km/h - Time = 20 / (x + 12) hours

For the second train: - Distance = 20 km - Speed = x km/h - Time = 20 / x hours

According to the given information, the first train takes 50 minutes less time than the second train. Since 1 hour is equal to 60 minutes, we can convert 50 minutes to hours by dividing it by 60: - 50 minutes = 50 / 60 hours = 5 / 6 hours

So, we can set up the equation: 20 / (x + 12) = 20 / x - 5 / 6

To solve this equation, we can cross-multiply and simplify: 20x = 20(x + 12) - 5(x + 12) / 6

Simplifying further: 20x = 20x + 240 - 5x - 60 / 6

Combining like terms: 20x - 20x = 240 - 60 / 6

Simplifying: 0 = 180 / 6

Since the left side of the equation is 0, this means that the equation has no solution. Therefore, there is no valid solution for the given problem.

Conclusion

Based on the given information, there is no valid solution for the problem of finding the speeds of the two trains.