Puzzles/Logic puzzles/Bridge Crossing

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Puzzles | Logic puzzles | Bridge Crossing


There are four people at one end of a bridge and they need to get across. The bridge is old and can only support two people at a time. It's night and one of the two must carry a flashlight. The four people have only one flashlight. Also, they move at different speeds. A group moves only as fast as its slowest member. The crossing times of the four are 1, 2, 5 and 10 minutes respectively.

How can they make it to the other side of the bridge in 17 minutes?

Solution