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Old 10-10-2007, 02:13 PM
jay_shark jay_shark is offline
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Join Date: Sep 2006
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Default Re: Solving problems in Reverse

Here is a probabilistic explanation for R. Gilbert's answer .

13/52 is the probability the first card is a diamond . This may also include the probability when the second card is a diamond or not .

The probability the first card isn't a diamond but the second card is :

39/52*13/51 .

These two events are mutually exclusive and we can add them directly .
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