# Thread:

1. ## I cant Get this... HELP>>>

How many distinct Permutations of the letters of the word OTTAWA begin and end with the letter T?

2. Originally Posted by wikji
How many distinct Permutations of the letters of the word OTTAWA begin and end with the letter T?

The number of permutations of a set with n elements is n!

since it needs to begin and end with t they can't move so we have 4!, but we want distinct permutations so we need to get rid of the double count of a's so we end up with

$\frac{4!}{2!}=\frac{24}{2}=12$
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