Bridge and torch
Four people must cross a bridge at night with a single torch. At most two cross at a time, and a pair moves at the slower person's pace. Their crossing times are 1, 2, 5, and 10 minutes. What is the minimum total time to get everyone across?
Show hints (2)+
- The torch must be carried back each time.
- Try to make the two slowest people cross together.
Answer
Reveal answer →Final answer
17
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Asked at: Optiver, Akuna Capital