document.write( "Question 1199902: What is the probability that if 11 letters are typed, no letters are repeated?
\n" ); document.write( "The probability that no letters are repeated is \n" ); document.write( "
Algebra.Com's Answer #833879 by ikleyn(52921)\"\" \"About 
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\n" ); document.write( "What is the probability that if 11 letters are typed, no letters are repeated?
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document.write( "We have 26 lowercase letters and 26 uppercase letters in English alphabet.\r\n" );
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document.write( "Assuming that we use lowercase letters only, there are  \"26%5E11\" possible words \r\n" );
document.write( "of the length 11.\r\n" );
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document.write( "Of them, the number of words with no repeating letters is  26*25*24*23*22*21*20*19*18*17*16\r\n" );
document.write( "(11 factors of integer numbers in descending order starting from 26, in all).\r\n" );
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document.write( "The probability do not have repeating letters is\r\n" );
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document.write( "    1 -  = \r\n" );
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document.write( "    = 1 - 0.084026 = 0.915974   (rounded).    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "A TWIN problem to it is a popular problem on finding the probability
\n" ); document.write( "that there is no coinciding birthdays in the group of 11 persons.\r
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\n" ); document.write( "\n" ); document.write( "See the lesson\r
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