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-   -   Answer is wrong (https://www.askmehelpdesk.com/showthread.php?t=186207)

  • Feb 20, 2008, 10:27 AM
    waqassiddiqui
    answer is wrong
    Q- Two cards are drawn in succession from a deck without replacement. What is the probability that both cards are greater than 2 and less than 8?

    My solution:
    probabilty = n/N
    n = 5 x 4
    N = 52 cards
    probability = 20 / 52


    BUT the answer is 95/663
  • Feb 20, 2008, 10:48 AM
    ISneezeFunny
    you got the first step down.

    there are 5 cards (per suit) that's between 2 - 8. (3, 4, 5, 6, and 7)

    there are 4 suits.

    so there are 20 cards out of 52 cards that you're looking for. That's for the FIRST pick.

    20/52

    second pick, you are left with 19 cards out of 51 cards.

    19/51

    (20/52)(19/51) = 95/663
  • Feb 22, 2008, 12:07 PM
    galactus
    That's a nice explanation given by I sneezefunny. You can also use combinations.


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