Posted by **Tony** on Wednesday, September 14, 2011 at 3:00am.

U2 has a concert that starts in 17 minutes and they must all cross a bridge to get there. All four men begin on the same side of the bridge. You must help them across to the other side. It is night. There is one flashlight. A maximum of two people can cross at one time. Any party who crosses, either 1 or 2 people, must have the flashlight with them.

The flashlight must be walked back and forth. It cannot be thrown and other tricks like that are not needed to solve the problem. The solution is simply a matter of allocating resources in a certain order. Each band member walks at a different speed. A pair must walk together at the rate of the slower man's pace:

Bono: 1 minute to cross

Edge: 2 minutes to cross

Adam: 5 minutes to cross

Larry: 10 minutes to cross

For example: if Bono and Larry walk across first, 10 minutes have elapsed when they get to the other side of the bridge. If Larry then returns with the flashlight, a total of 20 minutes have passed and you have failed the mission.

- brain teaser -
**Chris**, Monday, January 23, 2012 at 3:53pm
Bono (1) walks over with Edge (2), 2 minutes, Bono walks back, 1 minute (3 total), Larry (10) and Adam (5), walk across, 10 minutes (13 total), Edge Walks Back, 2 minutes (15 total), Edge and Bono walk back, 2 minutes (17 total)

## Answer This Question

## Related Questions

- algebra - four men qant to cross a bridge. they all begein on the same side. its...
- Math - Four people want to cross a bridge. They all begin on the same side. Itâ€™s...
- Algebra - Four people are on one side of a bridge. All of them need to cross a ...
- MATH - FOUR CYCLISTS A,B,C&D WANTS TO CROSS A BRIDGE BUT DUE TO BAD CONDITION OF...
- Math - There are four people that want to cross a bridge. Sam can cross in 1 ...
- Physics - Train A starts at 4 miles South of a bridge and heads North at a ...
- maths magic - There are A,B,C,D at one end of the bridge.they have to cross ...
- Math - Once there four boys who wanted to cross a street. They were all on the ...
- algebra - You live under a bridge that goes over a river. the underneath side of...
- algebra - You live under a bridge that goes over a river. the underneath side of...

More Related Questions