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Logical Puzzles Expert 4 min

Four people need to cross a bridge at night. Their crossing times are 1, 2, 5 and 8 minutes. At most two can cross at once and they must carry one torch. What is the minimum total time?

Hint
The two fastest people should be used to return the torch.

Answer

15 minutes.

Explanation

Use the two fastest people to transport the torch while the two slowest cross together.

Step-by-Step Solution

1 and 2 cross = 2.
1 returns = 1.
5 and 8 cross = 8.
2 returns = 2.
1 and 2 cross = 2.
Total = 15 minutes.
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