Permo Combo continues 13

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Permo Combo continues 13

by maihuna » Mon Aug 10, 2009 10:09 am
If all the words which can be made from word AGAIN and these words are written as in a dictionary, what will be the 50th word?

NAAGI
NAAIG
NAGIA
NAIGA
NAGAI
Charged up again to beat the beast :)

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by real2008 » Mon Aug 10, 2009 10:27 am
it should be NAAIG

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by prindaroy » Mon Aug 10, 2009 11:15 am
NAAIG is correct;

A _ _ _ _ = 4! = 24

G _ _ _ _ = 4!/2! = 12

I _ _ _ _ = 4!/2! = 12

so 48 words total and N has to be next so;

N A A G I will be 49

and N A A I G will be 50

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by knowledgeisatreasure » Mon Aug 10, 2009 1:09 pm
Hi,

Would you explain why do we need to divide by 2! if the question doesn't specify whether there is repetition or not, meaning redundancy is ok in this case.

Is it possible to get 120 words instead of 50 from the word AGAIN (5!) ?

Appreciate your answer.

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by prindaroy » Mon Aug 10, 2009 2:08 pm
It doesn't matter if the question states repetition or not. The point is permutations. How many ways can the word BAAA be arranged? the answer is 4!/3!

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by tohellandback » Mon Aug 10, 2009 9:34 pm
total number of words=5!/2!=60
words starting with N= 4!/2!= 12

49th word: NAAGI
50th word: NAAIG
B
The powers of two are bloody impolite!!