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Thread: Probability Cards

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    Probability Cards

    What is the probability of getting two cards belonging to two different suits when two cards are drawn at random from a pack of well shuffled cards comprising 52 cards?








    SPOILER: Official Answer 13/17

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    Within my grasp! ESeraph's Avatar
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    52*39/52*51

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    Grrr... arjmen's Avatar
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    P(2 cards selected from more than 1 suit) = 1 - P(2 cards selected from only 1 suit) = 1 - 4*(13C2)/(52C2) = 1 - (4*13*12)/(52*51) = 1 - 12/51 = 39/51 = 13/17

    OR more simply,

    (52/52)*[(13*3)/51] = 13/17

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    thnx guys

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    An Urch Guru Pundit Swami Sage 800Bob's Avatar
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    Easiest way to answer this one is to think of it this way. It doesn't matter what the first card is. Once one card has been drawn, there remain 51 cards, of which 39 are of a different suit. 39/51 = 13/17.

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