document.write( "Question 464846: a student takes a 20 question, multiple choice exam with five choices for each question. if the student is guessing, find the following probabilities getting every question but two wrong \n" ); document.write( "

Algebra.Com's Answer #318515 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 (guessing right) = .20 and q = .80
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document.write( "nCx =   |20C2 = 190
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document.write( "P(guessing 18 out of the 20 incorrectly) = 190(.20)^2(.80)^18 =.1369 \n" );
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