document.write( "Question 353553: in a shipment of 12 television sets 3 found out to be defective.In how many ways can a person take 5 sets which contains atleast 2 defective items. \n" ); document.write( "
Algebra.Com's Answer #252603 by Edwin McCravy(20056)\"\" \"About 
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document.write( "There are \"12 choose 5\" or 12C5 ways to select any 5 TV sets.\r\n" );
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document.write( "From this number we must subtract: \r\n" );
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document.write( "(1). the number of selections of 5 that contain no defective TV sets \r\n" );
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document.write( "as well as \r\n" );
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document.write( "(2). the number of selections of 5 that contain only 1 defective TV set.\r\n" );
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document.write( "We calculate (1) and (2)\r\n" );
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document.write( "(1). Choices of 5 with no defective TV sets:\r\n" );
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document.write( "     Since there are 12 sets and 3 are defective, there are 12-3 or 9\r\n" );
document.write( "     non-defective ones, so this is \"9 choose 5\", or 9C5.\r\n" );
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document.write( "(2). Choices of 5 with 4 non-defective sets and 1 defective set:\r\n" );
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document.write( "     \"9 choose 4\" times \"3 Choose 1\" or (9C4)(3C1)\r\n" );
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document.write( "Subtracting the number of choices of (1) and (2), which do not contain \r\n" );
document.write( "at least 2 defective TVs from the total number of choices of any 5\r\n" );
document.write( "TVs, we have:\r\n" );
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document.write( "12C5 - 9C5 - (9C4)(3C1)\r\n" );
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document.write( " 792 - 126 - (126)(3) = 288\r\n" );
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document.write( "That's the answer, 288.\r\n" );
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document.write( "Edwin

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