Another Card Game

Galilee · #1 10-07-2004, 07:44 PM

This has nothing to do with the internet or poker, let alone internet poker. But the other Card Game post seemed to go down alright, so here's another one!

Given:

All four aces out of a deck
One new car*
An impartial dealer
You

Problem:

The four aces are placed face down by the dealer - only he knows which card is which. You get to pick one - if you pick the Ace of Spades you get the car. But before the card you picked is flipped over, the dealer turns over two of the other three cards, revealing two aces naturally... but not the ace of spades! The dealer then gives you a choice: turn over the card you first picked, or change your mind and go for the final unseen card ... what do you do?

*a brand new Mini Cooper

SnakeRat · #2 10-07-2004, 07:48 PM

Go for the one I didn't pick.

GrannyMae · #3 10-07-2004, 07:54 PM

in 1965, i think lorinda posted this problem with boxes instead of cards.

please check back at least 5 archives before posting another probability game.

Thythe · #4 10-07-2004, 07:57 PM

This is just a rehashed monty hall problem. If you stick with the original card you have a 25% chance of winning. If you switch cards, you have a 75% chance of winning. Do you see why? (haha, just kidding, I've always wanted to use a 2+2 cliche).

jasonHoldEm · #5 10-07-2004, 07:58 PM

Always switch, you double your chances of winning.

EDIT: Not double I guess..."increase" your chances of winning.

This is the model I want...

Cubswin · #6 10-07-2004, 10:34 PM

Those nipples are small, dark and grossly misplaced

Rudbaeck · #7 10-08-2004, 07:04 AM

You triple your win chance by switching cards.

Isn't this problem part of elementary school probability by now?

Photoc · #8 10-08-2004, 07:17 AM

I feel a thread derailment coming on here! [img]/images/graemlins/shocked.gif[/img]

Galilee · #9 10-08-2004, 01:34 PM

Apologies if that was too old/easy! Yes, it is a variation on a classic puzzle, and yes, you always change cards. If anyone still cares, you have a 1 in 4 chance of picking the Ace of Spades on your first go, so you must have a 3 in 4 chance of getting it if you swap cards.

Lori · #10 10-08-2004, 01:42 PM

in 1965, i think lorinda posted this problem with boxes instead of cards.

Your memory is strong. That was one of lorinda's first 50 posts I think.

Lori