document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1058592>Question 1058592</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A sample of 230 observations is selected from a normal population for which the population standard deviation is known to be 26. The sample mean is 18.<BR>\n" );
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document.write( "a.	<BR>\n" );
document.write( "Determine the standard error of the mean. (Round your answer to 3 decimal places.)<BR>\n" );
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document.write( "  Standard error of the mean:<BR>\n" );
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document.write( "b.	<BR>\n" );
document.write( "Determine the 99% confidence interval for the population mean. (Use z Distribution Table.) (Round your answers to 3 decimal places.)<BR>\n" );
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document.write( "  Confidence interval between          and <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 #673673 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=673673\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The SEM is sigma/sqrt(n)=26/sqrt(230)=1.714<BR>\n" );
document.write( "That means that although the mean of the sampling distribution is the same, the SD is much less. It is very unlikely all of the 230 observations will be 1 SD to one side or the other of the mean.<BR>\n" );
document.write( "The 99% CI uses z=2.576<BR>\n" );
document.write( "z*SEM is the interval width is 4.415<BR>\n" );
document.write( "(21.585,30.415)<BR>\n" );
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