document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=437125>Question 437125</A>: <I><SPAN STYLE=\"word-break: break-all;\"> the final exam in a math coures consists of 40 multiple-choise question. each question has 4 possible answers, and only 1 of them is correct. an unprepared student makes random guesses for all of the answers. find the mean and standard deviation for the number of correct anwers for such student. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #302427 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=302427\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  the final exam in a math course consists of 40 multiple-choise question. each question has 4 possible answers, and only 1 of them is correct. an unprepared student makes random guesses for all of the answers. find the mean and standard deviation for the number of correct anwers for such student.<BR>\n" );
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document.write( "Binomial Problem with n=40 and p = 1/4<BR>\n" );
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document.write( "mean = np = (1/4)(40) = 10<BR>\n" );
document.write( "std = sqrt[npq] = sqrt[10*(3/4)] = 2.7386<BR>\n" );
document.write( "====================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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