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Homework Help: 4th Combinatorial problem

  1. Jul 18, 2007 #1
    1. The problem statement, all variables and given/known data
    A group comprising 6 peoiple is sitting around a table. Find the probability that two particular people are sitting next to each other.


    2. Relevant equations



    3. The attempt at a solution

    4!2!/5!=2/5 because total number of possibities is 5!. If 2 people are to be next to each other than there are 5 groups so 4! choices with each choice, one can swap the group of two. So times by 2!.


    BUt the answers suggested 1/5
     
  2. jcsd
  3. Jul 18, 2007 #2

    Dick

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    Some really dubious 'answers' are being suggested to you. The answer is clearly 2/5. Pick one of the particular people. There are 2 people sitting next to him and 3 not. The odds the other particular person is in the former group is 2/5.
     
    Last edited: Jul 18, 2007
  4. Jul 18, 2007 #3
    That is a nice way of doing it.
     
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