4 ms·
It becomes a lot clearer if you increase the number of goats. I have a deck of a billion cards, one entitles you to the car, the others have a picture of a goa
by Schroedingersat 4y ago
It becomes a lot clearer if you increase the number of goats.
I have a deck of a billion cards, one entitles you to the car, the others have a picture of a goat. You pick one at random but do not get to see it.
Of the remaining 999,999,999 cards, I discard 999,999,998 goats.
Do you want your initial card, or the remaining card in my deck?
Or to frame it another way, do you want the car iff you picked it first or iff you did not pick it first?
- tsimionescu 4y agoThe GP is not contesting this, they just think that the whole discarding/revealing of the goats is an unnecessarily complicated explanation for why this works. The way they put it, the strategy becomes obvious if you instead reformulate the problem like so: there are three doors with three different prizes. You get to pick one door, but are then given a choice: stick with your original choice, or choose to get the best prize from the other two doors. The solution (switch!) is more obvious in the second formulation. I have no idea if it's easier to convince someone else of the reasoning in the first formulation, or to convince them that the second formulation is equivalent to the original.