another puzzler
"Bill Graham" wrote in
:
I claqim there are two games. In the first game, you go to the studio,
pick a door, and then go home to wait and see if they call you and
tell you that you either won or lost. Your odds are only 1/3 of
winning this game. But if you play the second game, then you go to the
studio and mess around until the host opens up a door and shown you
the donkey behind it. then you can play the game with 50-50 odds of
winning. The only thing I have trouble explaining is why, in order to
play this second game with the better odds, you have to switch doors.
But, in fact, you do have to switch in order to switch games and take
advantage of the better odds.
It's not just 50/50. It's 67/33 in your favor.
Here's another super-simple explanation:
As Cecil Adams puts it (Adams 1990), "Monty is saying in effect: you can
keep your one door or you can have the other two doors."
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