document.write( "Question 426693: A math student guesses all the answers on a 15 question quiz.
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Algebra.Com's Answer #296805 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi
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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 = .57 and q =.43
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document.write( "nCx = 
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document.write( "P(getting at most 8 answers correct out of 15 questions)
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document.write( "  1 - P(9) - P(10) - P(11) - P(12) - P(13) - p(14) - P(15) = .4847
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document.write( " P(9) = 5005(.57)^9(.43)^6 for example would be P( 9 out of 15 correct)
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document.write( "  P(9) = 5005(.57)^9(.43)^6 = .20095
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document.write( " 1 - .20095 - - - - etc = .4847\r
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document.write( "Note: one may using a Binomial Distribution Calculator P(x ≤ 8) \n" );
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