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Homework Help: Choosing a committee from a class

  1. Aug 27, 2007 #1
    1. The problem statement, all variables and given/known data
    How many ways can a 5-member committee be chosen from a class with34 students?


    2. Relevant equations



    3. The attempt at a solution

    Using the formula from the book, I did 34! / (34-5)! and I got 33,390,720.

    This gives me the same answer as doing 34*33*32*31*30, but that's the Permutations method. I thought in Permutations the order mattered, and in combinations they did not. But the order doesn't matter here. But the Combinations method of 34!/(5!*(34-5)!) gives me 278256 ways. Which way is right??!
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Aug 27, 2007 #2
    The second way. The permutations dont matter here. The committee will be the same regardless of the order the members are chosen in. Hence, it will be 34!/(5!*(34-5)!).
     
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