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permutations & combinations

permutations & combinations

by Krishnan S -
Number of replies: 4

The letters of the word 'ZENITH' are written in all possible orders.

1. How many words are possible if all these words are written out as in a dictionary ?

2. What is the rank of the word 'ZENITH' ?

In reply to Krishnan S

Re: permutations & combinations

by Srinath Murthy -

Total number of words =no of words taking 1 letter + no of words taking 2 letters and so on + no of words taking all letters

ZENITH has all six letters. So no of words taking 1 letter + no of words taking 2 letters and so on + no of words taking 5 letters +6 letter words starting with E +6 letter words starting with H + 6 letter words starting with I +6 letter words starting with N + 6 letter words starting with T + 6 letter words starting with Z follwed by E and H + 6 letter words starting with Z follwed by E and I + 6 letter words starting with Z follwed by E, N and H + 6 letter words starting with Z follwed by E, N, I and H will come before it.

In reply to Srinath Murthy

Re: permutations & combinations

by Krishnan S -

Hi Srinath,

               Please explain "rank of the word" and how can i find it?

In reply to Krishnan S

Re: permutations & combinations

by Srinath Murthy -

If 3 words come before a word then its rank is 4 so the question is how many words come before ZENITH.

No. of words taking 1 letter + no of words taking 2 letters and so on + no of words taking 5 letters +6 letter words starting with E +6 letter words starting with H + 6 letter words starting with I +6 letter words starting with N + 6 letter words starting with T + 6 letter words starting with Z follwed by E and H + 6 letter words starting with Z follwed by E and I + 6 letter words starting with Z follwed by E, N and H + 6 letter words starting with Z follwed by E, N, I and H will come before it.