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The Bridge and Torch Riddle
four people, one torch, 17 minutes
4 people must cross a bridge at night with 1 torch. At most 2 can cross at a time, and anyone crossing needs the torch. They take 1, 2, 5 and 10 minutes to cross, and a pair moves at the slower person's speed. What is the fastest they can all get across?
Source: A classic puzzle, retold by INFINITE SUM and fact-checked against our curated notes
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