a simple application http://adundas.noemata.net/teamwork/montyhall.exe
about the problem http://en.wikipedia.org/wiki/Monty_Hall_problem "The Monty Hall problem is a puzzle involving probability, loosely based on the American game show Let's Make a Deal. The name comes from that of the show's host, Monty Hall. The problem is also called the Monty Hall paradox; it is a veridical paradox in the sense that the solution is counterintuitive."
