A passenger train and a freight train leave from the two places at the same time. After four hours of meeting, it takes seven hours for the passenger train to complete the whole journey, and 60 kilometers for the freight train per hour, two times

A passenger train and a freight train leave from the two places at the same time. After four hours of meeting, it takes seven hours for the passenger train to complete the whole journey, and 60 kilometers for the freight train per hour, two times

The truck went the whole way 1-1 / 7x4 = 1-4 / 7 = 3 / 7
The distance between the two places is 4x60 / 3 / 7 = 240 / 3 / 7 = 560 km