The Train Fly Problem - A Classic Math Puzzle

Channel: MindYourDecisions


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A fly, moving at 40 mph, zigzags back and forth between two trains, each moving at 20 mph. If the trains are 100 miles apart initially, how much distance will the fly travel? The genius mathematician John von Neumann was able to solve this problem instantly in his head. This video teaches a trick so you can solve the puzzle quickly too.

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