>>>
>>>Then you know that the correct answer is to switch.
>>
>>You double your odds by doing so...
>
>Right. I've tried to convince my boss, but he couldn't get passed the "but it's just 50/50". Even after giving him the card example with 2 jacks and one ace.
It is a little hard to grasp. Here's how I see it:
The chances of a correct first guess are 33%. The chance that your first guess is incorrect is 66%. This is the key. And Monty *knows* which of the other doors is a goat. That is also important.
So, by switching to the door Monty didn't open, you will be right 66% of the time.
Now, if Monte didn't know the correct answer, and if he opened one of the 2 doors at random, your boss is right. He has a 50/50 chance, *if* Monte opens a goat. However, 33% of the time Monte would open the winner, and the game would end.
Steve Gibson