# Four People on a Rickety Bridge

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Four people need to cross a rickety bridge at night. Unfortunately, they have only one torch and the bridge is too dangerous to cross without one. The bridge is only strong enough to support two people at a time. Not all people take the same time to cross the bridge. Times for each person:  1 min, 2 mins, 7 mins and 10 mins. What is the shortest time needed for all four of them to cross the bridge?

ravi Expert Asked on 13th July 2015 in

Copy of http://puzzlefry.com/puzzles/crossing-the-bridge-puzzle-bridge-and-torch-problem-2/

on 14th July 2015.

Solution to the problem is as follows:

Move
Time
A & B Cross with torch
2
A Return with torch
1
C & D Cross with torch
10
B Return with torch
2
A & B Cross with torch
2
————————
————–
Total Time
17

SherlockHolmes Expert Answered on 14th July 2015.

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