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OK, that's what the person said the first time I heard this riddle; however, I don't get how the probability works. Isn't it still 1/2 car?FrogDoc07 said:That's correct. Apparently I was wrong in my assumption that most people would want the car over a goat...
Stage 1: All doors unknown. 1/3 chance of winning car.
Goat is revealed behind Door 3 but is not replaced so no longer plays a comprehensive factor.
Stage 2: Only two doors, two prizes. Thus, 1/2 chance of winning car.
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This problem is exactly like having two black marbles and one red one in a bag.
Draw 1: 1/3 chance of getting red.
You draw a black. Whoops! You do not, however, place it back into the bag.
Draw 2: 1/2 chance of getting red. The previous draw has absolutely nothing to do with the current probability since it is completely removed from the domain.
What am I not getting?