document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=135935>Question 135935</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The lifetime of a certain brand of battery is known to have a standard deviation of 9 hours. Suppose that a random sample of 100  such batteries has a mean lifetime of 45.6 hours. Based on this sample, find a 95% confidence interval for the true mean lifetime of all batteries of this brand. Then complete the table below. \r<BR>\n" );
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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 95% confindence interval?\r<BR>\n" );
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document.write( "What is the upper limit of 95% confindence interval?\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 #99595 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=99595\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The lifetime of a certain brand of battery is known to have a standard deviation of 9 hours. Suppose that a random sample of 100 such batteries has a mean lifetime of 45.6 hours. Based on this sample, find a 95% confidence interval for the true mean lifetime of all batteries of this brand. 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.<BR>\n" );
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document.write( "x-bar = 45.6<BR>\n" );
document.write( "E = 1.96 = 2.178 \r<BR>\n" );
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document.write( "What is the lower limit of 95% confindence interval? 45.6-2.178 <BR>\n" );
document.write( "What is the upper limit of 95% confindence interval? 45.6+2.178<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.\r<BR>\n" );
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