document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=490487>Question 490487</A>: <I><SPAN STYLE=\"word-break: break-all;\">  A test consists of 90 multiple choice questions, each with five possible answers, only one of which is correct. Find the mean and the standard deviation of the number of correct answers. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #334127 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=334127\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A test consists of 90 multiple choice questions, each with five possible answers, only one of which is correct. Find the mean and the standard deviation of the number of correct answers.\r<BR>\n" );
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document.write( "Binomial Problem with n = 90 and p(correct) = 1/5<BR>\n" );
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document.write( "mean = np = 90(1/5) = 18<BR>\n" );
document.write( "Std = sqrt(npq) = sqrt(18*(4/5)) = 3.7947<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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