document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=214372>Question 214372</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please show work on how you solved confidence interval problem.  A sample of 20 pages was taken withreplacement from the 1,591-page phone directory Ameritech Pages Plus Yellow Pages.   On each page, the mean area devoted to display ads was measured (a display ad is a large block ofmulticolored illustrations, maps, and text).  The data (in sqaure milltimeters) are shown.  <BR>\n" );
document.write( "   0    260   356    403   536    0    268   369   428    536<BR>\n" );
document.write( " 268    396   469    536   162  338    403   536   536    130<BR>\n" );
document.write( "a.  Construct a 95 percent confidence innterval for the true mean.  b.  Why might normality be an issue here?  c.  What sample size would be needed to obtanin an error of =+ 10 square millimeters with 99 percent confidence?  d.  If this is not a reasonble suggest one that is  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #161965 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=161965\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Please show work on how you solved confidence interval problem.  A sample of 20 pages was taken withreplacement from the 1,591-page phone directory Ameritech Pages Plus Yellow Pages.   On each page, the mean area devoted to display ads was measured (a display ad is a large block of multicolored illustrations, maps, and text).  The data (in square millimeters) are shown.<BR>\n" );
document.write( "  <BR>\n" );
document.write( "   0    260   356    403   536    0    268   369   428    536\r<BR>\n" );
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document.write( " 268    396   469    536   162  338    403   536   536    130<BR>\n" );
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document.write( "a.  Construct a 95 percent confidence innterval for the true mean.\r<BR>\n" );
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document.write( "sample mean = 325.35 standard deviation = 180.34\r<BR>\n" );
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document.write( "standard error: t[s/sqrt(n)] = 2.086 </SPAN>\n" );
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