## 19. Tram

On one tram line, trams depart regularly every 10 minutes throughout the day. A tram takes one hour to travel from one end of the line to the other. A passenger boards a tram at one terminal stop and rides to the last stop of the tram; out of boredom, he looks out the window and counts the oncoming trams of the same route. How many tram sets will he count in total.
19. The passenger will encounter all the tram cars that departed from the other end of the tram line less than an hour before his departure; generally speaking, there are six such trains. He will also encounter all the trains that will depart from the opposite end of the line within the next hour; generally speaking, there are also six such trains. Therefore, the passenger will count a total of twelve tram cars on the way.

Special case. If the departure of the tram cars from both terminal stations occurs simultaneously, then our passenger will encounter only eleven cars on the way, but he will see one additional oncoming car at each of the terminal stations.

![](https://cdn.mathpix.com/cropped/2024_05_21_fe999c0fe2ad81fc5164g-211.jpg?height=725&width=1288&top_left_y=1602&top_left_x=384)