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The Fly Between Two Trains
the hard way and the easy way
Two trains start 100 miles apart and head toward each other, each at 50 miles per hour. A fly starts at one train, flying at 75 miles per hour, zooms to the other train, turns around instantly, and keeps zigzagging until the trains meet. How far does the fly travel?
Source: A classic puzzle, retold by INFINITE SUM and fact-checked against our curated notes
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