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Homework Help: 3rd Combinatorial problem

  1. Jul 18, 2007 #1
    1. The problem statement, all variables and given/known data
    In how many ways can the letters of the word POTATOES be arranged in a circle?

    2. Relevant equations
    n distinguishable objects can be arranged in a circle in (n-1)! ways.

    3. The attempt at a solution
    O and T both have two identical copies so it should be 7!/(2!2!)=1260

    But the answers suggested 150.

    Can't see where I made my mistake.
  2. jcsd
  3. Jul 18, 2007 #2
    Seems right to me...
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