posted by Jacob on .
There are four people that want to cross a bridge. Sam can cross in 1 minute, Joe can cross in 2, Jack can cross in 5, and Steve can cross in 10. They have one flashlight, and two can cross at a time, but they must go at the same pace. So if Steve and Sam cross together, they must go at 10 minutes. The partners must use a flashlight, and one must bring it right back. They must cross in 16 minutes or less. How?