Solve using the Gaussian Elimination and show all work.
Mike, Joe and Bill are Painting a fence. The painting can be finished if Mike and Joe work together for 4 hours and Bill works alone for 2 hours, or if Mike and Joe work together for 2 hours, and Bill works alone for 5 hours, or if Mike works alone for 6 hours, Joe works alone for 2 hours and Bill works alone for 1 hour. How much time would it take each man to paint the entire fence by himself?