Puzzle #02: Getting past the freight train
From New Scientist #3229, 11th May 2019 [link] [link]
A very long passenger train is heading along a single track railway behind a freight train composed of a locomotive and three freight trucks. They are approaching a station where the freight train is due to unload. To keep to its timetable, the passenger train needs to leave before the freight train will have had time to unload.
At the station, there is a siding that either train could drive into. The siding is large enough to hold a locomotive and one freight truck, or two freight trucks. Both trains have couplings at the front that allow them to push and pull trucks. How can the passenger train get past the freight train so that both can continue on their journey?