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Premutations problem help

  1. Feb 23, 2007 #1
    In how many ways can 5 distinct Martians, ten distinct Vesuvians and eight distinct Jovians wait together in line if no two Martains stand together>

    2. 10_p_5 = 10! & 5! but what about 8? and 2?

    3. 10! = 10*9*8*7*6*5*4*3*2*1
    8! = 8*7*6*5*4*3*2*1
    5! = 5*4*3*2*1
    10*9 = 90/2 = 45?

    I am so lost.. I am not a programmer..but required to take this class for my major!! Please anyone help me out?!?!
  2. jcsd
  3. Feb 23, 2007 #2
    consider a line of vesuvians and jovians and fill the martians into the gaps. That'll be the total possible ways of fitting in Martians so that no two matians stay together.
  4. Feb 23, 2007 #3

    I did that one already and I didn't like the answer. But thanks.
  5. Feb 23, 2007 #4
    what does that mean :confused:
  6. Feb 23, 2007 #5
    It means I did the chain with every 3rd position there is a Martian, but that does not tell me how to write the equasion to present the proper answer. If I factor out each element 5! = 120 * 10! = 3628800 *8! =40320
    which gives me an answer of 1.5801827328E15.
    Since we are working with combinations and Premutations I'm lost on which way to do the problem.
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