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#1
04-04-2007, 02:13 PM
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Simple Permutation problem
Problem is : How many ways can the letters of the word EXERCISES be arranged, when it must begin with a vowel.
I have 8!/3!2! + 8!/2!2! I believe this is the right answer the first fraction is when it starts with the letter I and the second is when it starts with the letter E. Now, do I have to multiply the one that starts with the letter E by 3 because there are 3 E's? Thank you very much, in advance. 
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#2
04-04-2007, 02:57 PM
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Re: Simple Permutation problem
Begins with E :
8!/(2!2!) Starts with an I : 8!/(3!2!) and now just add them . No , you don't multiply by anything . If you take any word with multiple letters like BOB , then to understand things better , it's recommended that you put indices to distinguish the letters . For instance B10B2 is the same word as B20B1 and so this is the reason why we divide 3! by 2! to avoid double counting .
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