document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1047800>Question 1047800</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 5.7   Suppose that the population standard deviation (sigma) for a normally distributed standardized test of achievement is known to be 7.20.  You can use these to estimate the standard error of the mean for a randomly drawn sample size of 16.  \r<BR>\n" );
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document.write( "  6  5    6  12   5  10  11  13<BR>\n" );
document.write( "12  10  9  20  23 28  20  18\r<BR>\n" );
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document.write( "But now suppose that we do not feel comfortable assuming that s = 7.20. Use the scores above to<BR>\n" );
document.write( "a.	estimate the standard error of the sample mean ()\r<BR>\n" );
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document.write( "b.	find the 95% confidence interval for the mean.<BR>\n" );
document.write( "      <BR>\n" );
document.write( "c. find the 99% confidence interval for the mean<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #663361 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=663361\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  Suppose that the population standard deviation (sigma) for a normally distributed standardized test of achievement is known to be 7.20. You can use these to estimate the standard error of the mean for a randomly drawn sample size of 16. <BR>\n" );
document.write( "6 5 6 12 5 10 11 13<BR>\n" );
document.write( "12 10 9 20 23 28 20 18 <BR>\n" );
document.write( "But now suppose that we do not feel comfortable assuming that s = 7.20. Use the scores above to<BR>\n" );
document.write( "a.	estimate the standard error of the sample mean ()<BR>\n" );
document.write( "s = 6.7<BR>\n" );
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document.write( "b.	find the 95% confidence interval for the mean.<BR>\n" );
document.write( "x-bar = 13<BR>\n" );
document.write( "ME = 1.96*13/sqrt(16) = 7.37<BR>\n" );
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document.write( "95% CI:: 13-7.37 < u < 13+7.37<BR>\n" );
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document.write( "c. find the 99% confidence interval for the mean<BR>\n" );
document.write( "x-bar = 13<BR>\n" );
document.write( "ME = 2.5758*13/sqrt(16) = 8.37<BR>\n" );
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document.write( "99% CI: 13-8.37 < u < 13+8.37<BR>\n" );
document.write( "--------------<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "--------- </SPAN>\n" );
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