document.write( "Question 1204338: An exam consists of 20 multiple choice questions, each with 5 answer choices. If a student guesses on every question, this a binomial experiment with the random variable \r
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Algebra.Com's Answer #840506 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "An exam consists of 20 multiple choice questions, each with 5 answer choices.
\n" ); document.write( "If a student guesses on every question, this a binomial experiment with the random variable
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\n" ); document.write( " Number of questions answered correctly
\n" ); document.write( "What is the probability that the student answers exactly 4 questions correctly?
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document.write( "For each question, the probability to answer correctly is   = 0.8;\r\n" );
document.write( "the probability to answer incorrectly is   = 0.2.\r\n" );
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document.write( "Since this experiment is binomial, the probability under the problem's question is\r\n" );
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document.write( "    P(4 of 20) =  =  = 1.30057E-08.  \r\n" );
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document.write( "ANSWER.  P(4 of 20) = 1.30057E-08.\r\n" );
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