document.write( "Question 175393: How many different permutations can you make with the letters in the word seventeen? \n" ); document.write( "
Algebra.Com's Answer #130530 by gonzo(654)\"\" \"About 
You can put this solution on YOUR website!
the general formula for a permutation of a set of x units out of a possible set of n units is given by the equation:
\n" ); document.write( "\"n%21%2F%28n-x%29%21\"
\n" ); document.write( "---
\n" ); document.write( "you have 9 possible letters, so n would = 9 in this case.
\n" ); document.write( "you will be extracting a set of 9 letters from this, so x would also be 9 in this case.
\n" ); document.write( "---
\n" ); document.write( "the number of possible ways this set of 9 letters can be arranged if order is important (permutation is an ordered set) are then given by the equation:
\n" ); document.write( "9! / (9-9)!
\n" ); document.write( "which becomes:
\n" ); document.write( "9! / 0!
\n" ); document.write( "which becomes:
\n" ); document.write( "9!
\n" ); document.write( "because 0! = 1
\n" ); document.write( "---
\n" ); document.write( "the resultant answer would be 362880
\n" ); document.write( "---
\n" ); document.write( "this answer assumes that the same letter can be used more than once.
\n" ); document.write( "---
\n" ); document.write( "the word seventeen has 4 e's and 2 n's
\n" ); document.write( "to distinguish between them you would have to label them differently.
\n" ); document.write( "something like:
\n" ); document.write( "e1, e2, e3, e4, e5
\n" ); document.write( "n1, n2
\n" ); document.write( "---
\n" ); document.write( "you can also assign numbers to each letter so that they show up as unique.
\n" ); document.write( "something like:
\n" ); document.write( "s = 1, first e = 2, v = 3, second e = 4, etc.
\n" ); document.write( "---
\n" ); document.write( "if multiple occurrences of the same letter are not allowed, then the problem becomes different.
\n" ); document.write( "---
\n" ); document.write( "the assumption here would be that multiple occurrences of the same letter count as one occurrence.
\n" ); document.write( "---
\n" ); document.write( "in that case, you have 5 unique letters to choose from.
\n" ); document.write( "those are:
\n" ); document.write( "s, e, v, n, t
\n" ); document.write( "---
\n" ); document.write( "the number of permutations you could make with these letters would be 5! which equals 120
\n" ); document.write( "---
\n" ); document.write( "to help you see this, take a word with smaller number of letters in it.
\n" ); document.write( "---
\n" ); document.write( "let the word \"see\" be the problem.
\n" ); document.write( "---
\n" ); document.write( "assuming the ssme letter can be used more than once, the number of permutations would be 3! = 6
\n" ); document.write( "let s = 1, first e = 2, second e = 3
\n" ); document.write( "this will make it easier to show:
\n" ); document.write( "the individual permutations are:
\n" ); document.write( "123
\n" ); document.write( "132
\n" ); document.write( "213
\n" ); document.write( "231
\n" ); document.write( "312
\n" ); document.write( "321
\n" ); document.write( "---
\n" ); document.write( "assume that multiple occurrences of the same letter count as one occurrence of that letter.
\n" ); document.write( "then the possible letters that can be used are s and e only.
\n" ); document.write( "this would be 2!
\n" ); document.write( "let s = 1, e = 2
\n" ); document.write( "permutations are:
\n" ); document.write( "12
\n" ); document.write( "21
\n" ); document.write( "---
\n" ); document.write( "the answer to your question is therefore:
\n" ); document.write( "---
\n" ); document.write( "if multiple occurrences of the same letter count as a separate occurrence of tht letter, then the number of permutations is 9! = 362880
\n" ); document.write( "---
\n" ); document.write( "if multiple occurrences of the same letter count as 1 occurrence of that letter, then the number of permutations is 5! = 120
\n" ); document.write( "---
\n" ); document.write( "
\n" ); document.write( "
\n" );