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Permo Combo continues 14

by maihuna » Mon Aug 10, 2009 10:14 am
If the different permutations of all the letter of the word EXAMINATION are listed as in a dictionary, how many words are there in this list before the first
word starting with E ?
Charged up again to beat the beast :)
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by real2008 » Mon Aug 10, 2009 10:35 am
is it 907200
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by prindaroy » Mon Aug 10, 2009 11:11 am
The answer is 10!/2!2!

All words beginning with A _ _ _ _ _ _ _ _ _ _

10 permutations with N and I repeated so 2!2!
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by knowledgeisatreasure » Mon Aug 10, 2009 1:25 pm
hello,


Would you explain why do we divide by( 2! multiplied by 2!) ??

Appreciate it.
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by tohellandback » Mon Aug 10, 2009 9:02 pm
only the words starting with A will come before words starting with E

total=10!/(2!*2!)
dividing by 2 factorial because here are two N's and two I's
The powers of two are bloody impolite!!
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