document.write( "Question 527436: In mathematics, a word is a list of letters which may or may not form an actual word in English ( or any other language). For example, aa, at, zz, so, ia, and pq are all 2 letter mathematical words. Suppose we wanted to count the total number of 4-letter mathematical words which have no repeating letters. \r
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\n" ); document.write( "\n" ); document.write( "Which method listed should we use? Combinations, Permutations, n(factor)k, Benford's Law \n" ); document.write( "
Algebra.Com's Answer #348897 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "I'm not sure what you mean by \"n(factor)k\" \r\n" );
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document.write( "I would answer \"permutations\", for the number of 4-letter \r\n" );
document.write( "\"words\" is P(26,4) or on\r\n" );
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document.write( "the TI-84, it's \r\n" );
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document.write( "26 nPr 4 \r\n" );
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document.write( "And it is calculated by\r\n" );
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document.write( "26×25×24×23 = 358800\r\n" );
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document.write( "Maybe that's what you mean by n(factor)k.  I am not familiar with\r\n" );
document.write( "\"n(factor)k\", but maybe you call that \"26(factor)4\".  I'm only familiar\r\n" );
document.write( "with calling it \"The number of permutations of 26 things taken 4 at\r\n" );
document.write( "a time\".\r\n" );
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document.write( "Regardless of what people call it, the number of 4-letter \"words\" \r\n" );
document.write( "without repeating letters is:\r\n" );
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document.write( "26×25×24×23 = 358800\r\n" );
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document.write( "Edwin
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