The Monty Hall solution is easily expained by a truth table. Name the doors A,B,C with the prize behind C.
Contestant's Monty's Contestant's
1st choice choice 2nd choice
___________ _______ ___________
A B A or C
B A B or C
C A or B C or B or A
__________ ___ ______
wins 1 2
If the contestant stays with his first choice, he has 1 chance in 3 to win. If he changes choices he has 2 chances in three to win.
posted by Robert Hatch
August 16, 2008