document.write( "Question 1194087: Six questions are in a multiple choice quiz. Each question has 5 possible answers. A student guesses at each question.
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Algebra.Com's Answer #826189 by ikleyn(52847) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "Six questions are in a multiple choice quiz. Each question has 5 possible answers.
\n" ); document.write( "A student guesses at each question.
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\n" ); document.write( "b) What is the student's expected number of correct answers?
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document.write( "Answering randomly, the probability to answer each separate multiple choice question correctly is ;\r\n" );
document.write( "answering incorrectly is .\r\n" );
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document.write( "The answers to 6 questions of the quiz are independent events.\r\n" );
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document.write( "So, we have a binomial distribution with 6 trials; the probability of success is   = 0.2 in each \r\n" );
document.write( "individual trial and the problem asks in part (a) about probability of 3 or more success trials.\r\n" );
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document.write( "The formula is\r\n" );
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document.write( "    P = P(3) + P(4) + P(5) + P(6) =  = .\r\n" );
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document.write( "     It can be calculated manually, or using technology.\r\n" );
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document.write( "     To facilitate calculations, I used online calculator at this site  https://stattrek.com/online-calculator/binomial.aspx\r\n" );
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document.write( "     It provides nice instructions  and  a convenient input and output for all relevant options/cases.\r\n" );
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document.write( "          The resulting number is P = 0.09888  (rounded).    \r\n" );
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document.write( "It is the  ANSWER  to question (a).\r\n" );
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document.write( "For question (b), math expectation of binomial distribution is  E = n*p = 6*0.2 = 1.2.\r\n" );
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\n" ); document.write( "\n" ); document.write( "If you want to see many similar (or different) solved problems, look into the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Simple and simplest probability problems on Binomial distribution \r
\n" ); document.write( "\n" ); document.write( "    - Typical binomial distribution probability problems \r
\n" ); document.write( "\n" ); document.write( "    - How to calculate Binomial probabilities with Technology (using MS Excel) \r
\n" ); document.write( "\n" ); document.write( "    - Solving problems on Binomial distribution with Technology (using MS Excel) \r
\n" ); document.write( "\n" ); document.write( "    - Solving problems on Binomial distribution with Technology (using online solver) \r
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\n" ); document.write( "\n" ); document.write( "After reading these lessons, you will be able to solve such problems on your own, \r
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