document.write( "Question 1151076: You own 8 different novels. How many ways can a shelf arrangement of 4 of the novels be formed \n" ); document.write( "

Algebra.Com's Answer #772690 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "In all, there are 8*7*6*5 = 1680 different arrangements.\r\n" );
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document.write( "It is the product of 4 integer factors, in descending order, starting from the biggest factor 8.\r\n" );
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document.write( "The standard mantra to solve this (and many other similar problems) is THIS :\r\n" );
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document.write( "    There are 8 ways to select the first book;\r\n" );
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document.write( "    then there are 7 ways to select the second book from 7 remaining books;\r\n" );
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document.write( "    then there are 6 ways to select the third book from 6 remaining books;\r\n" );
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document.write( "    and finally, there are 5 ways to select the fourth book from 5 remaining books.\r\n" );
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