Question 573257: I need some help getting this problem set up.I know one has to travel back and forth so that limits to one at a time to cross at the slowest pace.Just getting confused.
Four people are trying to cross a bridge in the dark. The bridge is old, and can only hold two of the people at any one time. They have only one flashlight, which must be carried by someone each time the bridge is crossed. The flashlight is weak, so it is not possible to stand in the middle of the bridge and guide someone across. Each person must walk across the bridge and either carry the light or walk with someone who is carrying the light. The fastest person can cross the bridge in one minute, the second fastest needs two minutes, the third fastest crosses in five minutes, and the slowest takes ten minutes. What is the shortest amount of time that all four can cross the bridge.
Answer by scott8148(6628) (Show Source):
You can put this solution on YOUR website! the two fastest cross and one brings back the light
the two slowest cross, and the fastest person (from the first crossing) brings back the light
the two fastest cross for the last time
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