Question

от станции а по направлению к станции в отошел товарный поезд со скоростью 30 км\ч через 0,5 часов от станции А в том же направлении отошел пассажирский поезд.С какой скоростью должен двигаться пассажирский поезд что бы догнать товарный на станции В . Расстояние между станциями 45км

Answer 1

1) За 0,5 часа тов. поезд проехал 36*0,5=18км. скорость сближения=72-36=36 км\ч. , отсюда: 
время=18/36=0,5часа. 

Answer 2

Problem Analysis

We are given that a freight train departs from station A with a speed of 30 km/h. After 0.5 hours, a passenger train departs from the same station A in the same direction. We need to determine the speed at which the passenger train should travel in order to catch up to the freight train at station B. The distance between the two stations is 45 km.

Solution

To solve this problem, we can use the formula: speed = distance / time.

Let's calculate the time it takes for the freight train to reach station B: - Distance: 45 km - Speed: 30 km/h - Time = distance / speed = 45 km / 30 km/h = 1.5 hours

Since the passenger train departs 0.5 hours after the freight train, it has to cover the same distance in 1 hour to catch up to the freight train at station B.

Let's calculate the speed at which the passenger train should travel: - Distance: 45 km - Time: 1 hour - Speed = distance / time = 45 km / 1 hour = 45 km/h

Therefore, the passenger train should travel at a speed of 45 km/h in order to catch up to the freight train at station B.

Answer

The passenger train should travel at a speed of 45 km/h in order to catch up to the freight train at station B.

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