document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1159555>Question 1159555</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The breaking strengths of cables produced by a certain manufacturer have a standard deviation of 94 pounds. A random sample of 80 newly manufactured cables has a mean breaking strength of 1800 pounds. Based on this sample, find a 99% confidence interval for the true mean breaking strength of all cables produced by this manufacturer. Then complete the table below.<BR>\n" );
document.write( "Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place.\r<BR>\n" );
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document.write( "What is the lower limit of the 99% confidence interval?	<BR>\n" );
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document.write( "What is the upper limit of the 99% confidence interval?	<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 #782623 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=782623\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 99% CI for mean is sample mean+/- z(0.995)*sigma/sqrt(n)<BR>\n" );
document.write( "half-interval is 2.576*94/sqrt(80)<BR>\n" );
document.write( "=27.07 or 27.1 pounds<BR>\n" );
document.write( "99%CI is (1772.9, 1827.1) pounds, the lower and the upper limit respectively </SPAN>\n" );
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