document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1206687>Question 1206687</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A student takes a 40-question multiple-choice exam but did not study and randomly guesses each answer. Each question has three possible choices for the answer. Find the probability that the student guesses more than 75% of the questions correctly. (Round your answer to three decimal places. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #844272 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52874)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=844272\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "A student takes a 40-question multiple-choice exam but did not study and randomly guesses each answer. <BR>\n" );
document.write( "Each question has three possible choices for the answer. Find the probability that the student guesses <BR>\n" );
document.write( "more than 75% of the questions correctly. (Round your answer to three decimal places.<BR>\n" );
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document.write( "This is a binomial experiment with n= 40 trials and p= 1/3 = 0.333333333 probability \r\n" );
document.write( "of the individual success  for each question, separately.\r\n" );
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document.write( "They want you determine the probability of 31 or more successes(correct answers). \r\n" );
document.write( "(More than 75% correct answers of 40 questions means 31 or more correct answers).\r\n" );
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document.write( "You can use regular calculator TI-83/84 with standard function binomcdf, or Excel function BINOM.DIST,  \r\n" );
document.write( "or free of charge online calculator https://stattrek.com/online-calculator/binomial.aspx\r\n" );
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document.write( "With only three decimals, the <U>ANSWER</U> is  P = 0.000.\r\n" );
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document.write( "Solved.\r<BR>\n" );
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document.write( "This request to round with 3 decimal places does not work in this problem and is inapplicable.\r<BR>\n" );
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document.write( "A real probability is about  0.0000000018  (obtained by using BINOM.DIST in Excel).\r<BR>\n" );
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document.write( " </SPAN>\n" );
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