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    NEED HELP URGENT! Probability Question




    How can we arrange 10 boys and 15 girls in such way that no two boys are adjacent to each other?

    Please help math geniuses.

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    Re: NEED HELP URGENT! Probability Question

    The boys need to arranged like this:

    _B_B_B_B_B_B_B_B_B_B_

    and the remaining 15 girls have to go into the 11 blank spots. The first or last blank could be left empty, but there has to be at least one girl in each of the 9 blank spots between the boys

    _BG_BG_BG_BG_BG_BG_BG_BG_BG_BG_

    That leaves 6 girls that can go into any of the 11 spots.

    The number of different ways to distribute n indistinguishable girls into k distinguishable spots is {{n + k - 1}\choose{k - 1}}

    {{6 + 11 - 1}\choose{11 - 1}} = {{16}\choose{10}} = 8008
    Last edited by asterisk; 10-23-2013 at 11:16 AM.

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    Re: NEED HELP URGENT! Probability Question

    I'm guessing we're assuming that they be in a line and that it's not a circle or a square or something else...
    I don't have emotions and sometimes that makes me very sad.

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    Re: NEED HELP URGENT! Probability Question

    Yes, Its on straight row.

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    Re: NEED HELP URGENT! Probability Question


    Do you have an actual problem or question you can post, which may help to eliminate some of the vagaries.
    Stop cowardice, ban guns!

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