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Homework Help: Problem Solving Combinations

  1. Nov 19, 2009 #1
    1. The problem statement, all variables and given/known data
    There are 15 boys and 19 girls in a room.
    a) Find the number of different groups that contain exactly four girls and five boys.
    b) How many groups of 14 have an equal number of boys and girls?
    c) How many groups of 5 have more boys than girls?

    2. Relevant equations

    3. The attempt at a solution
    a) C(19,4) * C(15,5)

    b & c I have no idea where to start.
  2. jcsd
  3. Nov 19, 2009 #2


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    Isn't b just like a? If you have 14 people with equal numbers of boys and girls then how many boys? Girls?

    And for c, what are the choices that qualify from 5-0, 4-1, 3-2, 2-3, 1-4, 0-5. Figure them out and add them up.
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