document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=450023>Question 450023</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose a student takes a multiple choice test with 10 questions and he randomly guesses the answers (say he forgot to study). Each questions has five choices but only one right answer. What is the probability that he gets at least 7 right out of the 10 questions.<BR>\n" );
document.write( "I am unsure how to work this problem. <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #309604 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=309604\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Suppose a student takes a multiple choice test with 10 questions and he randomly guesses the answers (say he forgot to study). Each questions has five choices but only one right answer. What is the probability that he gets at least 7 right out of the 10 questions.<BR>\n" );
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document.write( "Binomial Problem with n = 10 and p = 1/5<BR>\n" );
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document.write( "P(5<= x <=10) = 1-P(0<= x <=4) = 1-binomcdf(10,1/2,4) = 0.6230<BR>\n" );
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document.write( "I used a TI-84 to get the numbers.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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