document.write( "Question 876613: Evaluate C(9,7) \n" ); document.write( "

Algebra.Com's Answer #528886 by Edwin McCravy(20077) $\"\"$ $\"About$

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document.write( "Let's look at a different example so you'll learn how: \r\n" );
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document.write( "C(12,5)\r\n" );
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document.write( "The 12 is the number you start the numerator with.\r\n" );
document.write( "The 5 is the number you start the denominator with.\r\n" );
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document.write( "The 5 also tells you how many factors you need in the numerator,\r\n" );
document.write( "as well as in the denominator. (You always have the same number\r\n" );
document.write( "of factors in the numerator and denominator):\r\n" );
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document.write( "The numerator begins with 12 and has 5 factors, each one is\r\n" );
document.write( "one less than the one before it, like this:\r\n" );
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document.write( "12×11×10×9×8\r\n" );
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document.write( "The denominator begins with 5 and also has 5 factors, each one is\r\n" );
document.write( "one less than the one before it, like this:\r\n" );
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document.write( "5×4×3×2×1\r\n" );
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document.write( "So C(12,5) = \r\n" );
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document.write( "Cancel the 12 in the top with the 4×3 in the bottom, like this:\r\n" );
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document.write( "C(12,5) = \r\n" );
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document.write( "You can also cancel the 10 in the top with the 5×2 in the bottom\r\n" );
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document.write( "C(12,5) =  \r\n" );
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document.write( "so the answer is\r\n" );
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document.write( "C(12,5) = 11×9×8 = 792\r\n" );
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document.write( "You can always cancel the denominator entirely into the numerator.\r\n" );
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document.write( "-----------------------------------\r\n" );
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document.write( "Edwin

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