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Probability Q

Discussion in 'DAT Discussions' started by DentalKitty, Apr 24, 2007.

  1. DentalKitty

    DentalKitty 5+ Year Member

    202
    0
    Mar 12, 2007
    I just made this problem up so please tell me if it doesn't make sense.

    If you have a deck of cards, how many ways can you have 3 jacks in a hand of 5 cards?

    *edit* I mean different hands of 5 cards that contain 3 jacks

    Would it be 49*48*3*2*1? Or 4*3*2*49*48? Something else? I'm just trying to think of things they could ask, thanks!
     
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  3. Streetwolf

    Streetwolf Ultra Senior Member Dentist 7+ Year Member

    1,801
    5
    Oct 25, 2006
    NJ
    (4 choose 3) --> chooses the 3 suits of the Jacks in your hand
    (48 choose 2) --> chooses the last 2 cards in your hand. Use 48 because you have accounted for 3 Jacks, and you don't want a 4th Jack. This leaves 48 cards in the deck to choose from.

    4 choose 3 = 4
    48 choose 2 = 1,128

    4x1128 = 4,512

    Of course this includes both 3 of a kind and full house hands.
     
  4. DentalKitty

    DentalKitty 5+ Year Member

    202
    0
    Mar 12, 2007
    Oh I see now. You have to treat each piece separately and then multiply. Thanks a lot!
     

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