document.write( "Question 944803: A total of 72 different two-item outfit permutations can be created from a pile of clothes containing\r
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Algebra.Com's Answer #576140 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "We can choose the first item in n ways.\r\n" );
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document.write( "For each of those n ways to choose the first item,\r\n" );
document.write( "we can choose the second item any of the n-1 remaining ways.\r\n" );
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document.write( "That's n(n-1) ways.\r\n" );
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document.write( "For that number to be 72 the solution would be the solution\r\n" );
document.write( "to the equation\r\n" );
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document.write( "        n(n-1) = 72\r\n" );
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document.write( "        nē - n = 72 \r\n" );
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document.write( "   nē - n - 72 = 0\r\n" );
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document.write( "(n - 9)(n + 8) = 0\r\n" );
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document.write( "n-9=0;  n+8=0\r\n" );
document.write( "  n=9;    n=-8\r\n" );
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document.write( "Ignore the negative answer.\r\n" );
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document.write( "Solution:  9 garments.\r\n" );
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document.write( "Edwin
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