The Fly and the Trains
Two trains 100 miles apart head toward each other, each traveling at 50 mph. A fly leaves one train at 75 mph, flies to the other, turns around instantly, and repeats until the trains meet. What total distance, in miles, does the fly travel?
Related problems & prerequisites
Worth solving first
- The Hundred Lockers 5.0/10
Source: Classic puzzle in wide circulation, famous for the anecdote in which it was posed to John von Neumann. Statement written for AxiomIQ.