1. Changing your mind gives you the opposite of your original choice. << once you get this the rest is obvious 2. Your original choice gives you a goat 2/3 of

1. Changing your mind gives you the opposite of your original choice. << once you get this the rest is obvious 2. Your original choice gives you a goat 2/3 of the time and a car 1/3 of the time. 3. So by switching you get a car 2/3 of the time and a goat 1/3 of the time.