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Math Help - number of ways a switch can be set

  1. #1
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    number of ways a switch can be set

    if 8 switches can set to position a or b and an equal amount of switches are set to a as to b. How many ways could this be done?
    i though you could do this with \frac{8!}{4!.4!} but i got the wrong answer.

    D: i suck at probability
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  2. #2
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    Quote Originally Posted by renlok View Post
    i though you could do this with \frac{8!}{4!.4!} but i got the wrong answer.
    There are two possiblities for each of eight switches: 2^8.
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  3. #3
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    yeah but 4 switches have to be a and 4 have to be b
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  4. #4
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    Quote Originally Posted by renlok View Post
    yeah but 4 switches have to be a and 4 have to be b
    Well then it is \frac{8!}{(4!)^2}.
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