🚀 go-pugleaf

don@perseus.spk.wa.us (Donald Byrne) writes:

>So unless I'm not seeing the game properly it seems to me the 
>final results should be 50%.
>     Now explain why all of you say 66% of a chanch if he changes to the 
>other one of the remaining two??
>     I remain confused??

The initial odds that you guessed right are 33%, as your first guess is
random.  That means there's a 67% chance the prize is between one of the
other 2 doors.  Now Monty always reveals a "goat" door, so this gives you
*new* information, the prize is not behind the "goat" door he reveals.  Since
your initial guess is still 33% at being correct (revealing the goat does
NOT tell you anything about your door as Monty can *always* reveal a goat)
this means the remaining door is 67% at being correct.

Or change the rules a little.  After you pick a door, Monty, instead of
revealing a "goat", offers a choice of switching your door for BOTH the other
doors, but you then have to give Monty a "goat".  Do you switch?

This actually works out to be the same game, just described differently.

-Mike