document.write( "Question 812842: Rafael is taking a test that contains a section of 12 true-false questions. How many of the possible groups of answers to these questions have exactly 8 correct answers of false?
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Algebra.Com's Answer #489371 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi,
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document.write( "12 true-false questions.
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document.write( "Note: The probability of x successes in n trials is: 
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document.write( "P = nCx*  where p and q are the probabilities of success and failure respectively. 
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document.write( "In this case p & q are = 1/2 or .5
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document.write( "nCx = 
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document.write( "P(8 false answers) = 12!/8!4! (.5)^8(.5)^4 = 495(.5)^8(.5)^4 = .1208 \n" );
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