[ohnonotthat]

If someone offers to bet you $1,000 at even money that you cannot guess the exact card ONCE they either hate money or love you.

If you are given 52 chances and need only succeed once your chance of winning this bet is excellent.

The principle is the same as that used to calculate the odds of AK flopping a pair (or better), or of a pocket pair flopping a set (or better).

Do not add the possibilities of succeeding; multiply the chances of failing - and subtract the answer from "1".

1- (51/52 to the 52nd power) will do it; it's called "multiplication of negative expectation".

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I assume you were joking when you asked whether it mattered how you chose the card you used for your guess ?

If you were not [joking], here's a hint.

- It does not matter.

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Oops, I just noticed that Aaron already responded. Expect his reply to be clearer and likely more concise than mine but in this one case it's doubful he got it any righter than I did - this is stats 101 stuff.

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Pascal is alleged to have gotten rich betting people they could not roll a 6 on one die if given 4 tries then to have gone broke betting they could not roll 6-6 using two dice if given 24 tries.

5 / 6 to the 4th is .48225 (chance of getting at least one 6)

35/36 to the 24th is .50896 (chance of getting at least one 6-6

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He too tried adding the chances of success rather than multiplying the chances of failure.

Then again, he was French. [img]/images/graemlins/smirk.gif[/img]