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Homework Help: I want check my answers

  1. Mar 4, 2010 #1
    Q : Suppose 9 cards are number with the 9 digits from 1 to 9 . A 3-card hand is dealt, 1 card at a time . How many hands are possible where :

    1 ) Order is taken into consideration ?

    2 ) order is not taken into considreation ?


    ----------Ansewr >>


    1 - 9C3 X 9C1 = 84 X 9 = 756

    2 - 9P3 X 9P1 = 504 X 9 = 4536
     
  2. jcsd
  3. Mar 4, 2010 #2

    vela

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    Could you please elaborate on your thinking behind your answers?

    You have C and P backwards. Combinations is when you don't care about the order; permutations is when you do. "123" and "321" are the same combination, but they are two possible permutations of 1, 2, and 3.


     
  4. Mar 4, 2010 #3
    Is my answer correct ?
     
  5. Mar 4, 2010 #4

    statdad

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    read vela's post.
     
  6. Mar 4, 2010 #5
    The ansewr now correct ?

    1 - 9P3 X 9P1 = 504 X 9 = 4536

    2 - 9C3 X 9C1 = 84 X 9 = 756
     
  7. Mar 5, 2010 #6

    vela

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    No, they are not.
     
  8. Mar 5, 2010 #7
    Help me Give me the answer
     
  9. Mar 5, 2010 #8

    Hurkyl

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    No .
     
  10. Mar 5, 2010 #9
    I tay agine

    1 - 9C2 X 9C1 = 36 X 9 = 324

    2 - 9P2 X 9P1 = 72 X 9 = 648
     
  11. Mar 5, 2010 #10

    Hurkyl

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    Please elaborate on your thinking behind your answers?
     
  12. Mar 5, 2010 #11
    I can't try more thanks all
     
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