document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1156815>Question 1156815</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Use the confidence level and sample data to find a confidence interval for estimating the population μ. Round your answer to the same number of decimal places as the sample mean. (Sigma known)\r<BR>\n" );
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document.write( "a) A laboratory tested 82 chicken eggs and found that the mean amount of cholesterol was 228 milligrams with σ = 19.0 milligrams. Construct a 95% confidence interval for the true mean cholesterol content, μ, of all such eggs.\r<BR>\n" );
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document.write( "b) Write an interpretation. (Write answer on paper)\r<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 #779575 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=779575\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> sigma known so use 1.96 for z<BR>\n" );
document.write( "half-interval is1.99*19/sqrt(82)=4.11\r<BR>\n" );
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document.write( "the 95% CI is (224 mg, 232 mg)\r<BR>\n" );
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document.write( "The true value of the mean is unknown and unknowable, but we are 95% confident that it lies in the interval.\r<BR>\n" );
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document.write( "If we were to construct 100 such intervals like this one, the true mean would lie in 95 of them. We would not know which 95.<BR>\n" );
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