document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1040405>Question 1040405</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What is the 90% confidence interval for the variance of exam scores for 28 algebra students, if the standard deviation of their last exam was 12.7? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #655393 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=655393\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> [<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28%28n-1%29s%5E2%29%2FX%5E2%5Balpha%2F2%5D ALIGN=MIDDLE  ALT=\"%28%28n-1%29s%5E2%29%2FX%5E2%5Balpha%2F2%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28%28n-1%29s%5E2%29%2FX%5E2%5B1-alpha%2F2%5D ALIGN=MIDDLE  ALT=\"%28%28n-1%29s%5E2%29%2FX%5E2%5B1-alpha%2F2%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" > ]\r<BR>\n" );
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document.write( "=[<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2827%2A12.7%5E2%29%2FX%5E2%5B0.05%5D ALIGN=MIDDLE  ALT=\"%2827%2A12.7%5E2%29%2FX%5E2%5B0.05%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2827%2A12.7%5E2%29%2FX%5E2%5B0.95%5D ALIGN=MIDDLE  ALT=\"%2827%2A12.7%5E2%29%2FX%5E2%5B0.95%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" > ]\r<BR>\n" );
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document.write( "=[<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4354.83%2F40.113 ALIGN=MIDDLE  ALT=\"4354.83%2F40.113\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4354.83%2F16.151 ALIGN=MIDDLE  ALT=\"4354.83%2F16.151\"   DISABLED_style= \"max-width:90%; height:auto;\" > ]\r<BR>\n" );
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document.write( "= [108.564, 269.632]\r<BR>\n" );
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document.write( "where <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=X%5E2%5Balpha%2F2%5D+ ALIGN=MIDDLE  ALT=\"X%5E2%5Balpha%2F2%5D+\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the chi-square distribution with df 28-1 = 27, and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=alpha+=+0.10 ALIGN=MIDDLE  ALT=\"alpha+=+0.10\"   DISABLED_style= \"max-width:90%; height:auto;\" >. </SPAN>\n" );
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