SOLUTION: How many permutations are there in the letters of the word COCKROACH

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Question 975511: How many permutations are there in the letters
of the word COCKROACH
Answer by Edwin McCravy(20059) About Me  (Show Source):
You can put this solution on YOUR website!
COCKROACH

It's a 9-letter word, and if none of the letters looked alike the answer would
be 9!.  However there is no way to tell the difference between two arrangements
that just have the C's or the O's switched around.

So we must divide 9! by the number of ways the 3 C's can be rearranged within
any given permutation, which is 3!, and also we must divide by the number of
ways the 2 O's can be swapped, which is 2!.

Answer: 9%21%2F%283%212%21%29=30240

Edwin