document.write( "Question 1098955: A shelf has 7 probability books and 9 electonics books. Find the probability that 5 particular probability books will be together. \n" ); document.write( "
Algebra.Com's Answer #713430 by Edwin McCravy(20055)\"\" \"About 
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document.write( "Altogether there are 16 books.\r\n" );
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document.write( "There are 5 particular probability books and 11 other books.\r\n" );
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document.write( "Think of making a \"book bundle\" by tying a rope around the 5 \r\n" );
document.write( "particular probability books.\r\n" );
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document.write( "Then we have 12 \"things\" to arrange, 11 other books and 1 \r\n" );
document.write( "\"book bundle\".\r\n" );
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document.write( "There are 12! ways to arrange those 12 \"things\" on the shelf.\r\n" );
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document.write( "But there are 5! ways the 5 particular probability books can\r\n" );
document.write( "be arranged within the \"book bundle\".\r\n" );
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document.write( "So the number of ways to arrange the books successfully is 12!5!  \r\n" );
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document.write( "That's the numerator of the desired probability.\r\n" );
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document.write( "The denominator of the desired probability is the number of ways \r\n" );
document.write( "the 16 books can be arranged on the shelf, which is 16!\r\n" );
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document.write( "So the desired probability is \"%2812%215%21%29%2F16%21\", which simplifies\r\n" );
document.write( "to \"1%2F364\".\r\n" );
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document.write( "Edwin
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