Larry, Curly, and Moe are three friends who have recently bought a bookcase, which they must assemble. If Larry and Curly work together, they can build a bookcase in 2 hours. If Curly and Moe work together, they can build a bookcase in 1 2/3 hours. If Larry, Curly, and Moe all work together, they can build a bookcase in 1 hour.
If Larry and Moe work together, how long would it take them to build the bookcase?