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Homework Help: Flags on a Pole

  1. Sep 15, 2011 #1
    Find the number of way to place m flags on n distinct poles with at least one flag on each pole if the flags are identical. What if the flags are distinct.

    For the first part I said that there were
    n[itex]^{m-n}[/itex]

    because if you have m flag and you need each pole to have a flag you have m-n flags left. From those remaining flags we can put them on n poles.


    For the second part I just did the cases if there were 2 3 and 4 poles with a small number of balls to see if I could find a pattern and this is what I got

    (n!)*[itex]\frac{(m+n-1)!}{(2n-1)!}[/itex]

    but I am not sure if that is anywhere close to the right answer


    My question is are these answers right?
     
    Last edited: Sep 15, 2011
  2. jcsd
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