document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=884420>Question 884420</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The final exam in a sociology course consists of 100 multiple-choice questions. Each question has five possible answers, and only one of them is correct. An unprepared student makes random guesses for all of the answers. <BR>\n" );
document.write( " Find the mean and standard deviation for the number of correct answers for such students.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #534295 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=534295\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The final exam in a sociology course consists of 100 multiple-choice questions. Each question has five possible answers, and only one of them is correct. An unprepared student makes random guesses for all of the answers. <BR>\n" );
document.write( "Find the mean and standard deviation for the number of correct answers for such students. <BR>\n" );
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document.write( "mean = np = 100(1/5) = 20<BR>\n" );
document.write( "std = sqrt(npq) = sqrt(20(4/5)) = sqrt(16) = 4<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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