document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1167730>Question 1167730</A>: <I><SPAN STYLE=\"word-break: break-all;\">            Q1  Q2   Q3  Q4<BR>\n" );
document.write( "Pre-Cal    77  89   91  99\r<BR>\n" );
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document.write( "Rule: Round up the computed mean and round-off the computed variance and standard deviation into 2 decimal places)<BR>\n" );
document.write( "a. mean score = 89.00<BR>\n" );
document.write( "b. Σ(x-mean)^2 = 248<BR>\n" );
document.write( "c. variance = 82.67<BR>\n" );
document.write( "d. standard deviation = 9.09\r<BR>\n" );
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document.write( "can you check my answer if it is correct base on the rule? thank you. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #792326 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=792326\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> not sure what the rule is, however:\r<BR>\n" );
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document.write( "i get:\r<BR>\n" );
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document.write( "mean = sum(x) / 4 = 89<BR>\n" );
document.write( "sum of squared deviations from the mean = sum(x-m)^2 = 248\r<BR>\n" );
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document.write( "population variance = 248/4 = 62<BR>\n" );
document.write( "population standard deviation = sqrt(62) = 7.874007874\r<BR>\n" );
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document.write( "sample variance = 248/3 = 82.66666667<BR>\n" );
document.write( "sample standard deviation = 9.092121131\r<BR>\n" );
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document.write( "what you are showing is the sample variance and sample standard deviation.\r<BR>\n" );
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document.write( "if that's what you wanted to show, then you got the right answers.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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