document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=435211>Question 435211</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A simple random sample of 101 light bulbs had a mean life of 576 hours with a standard devation of 34 hours. construct a 90 percent confidence interval for the mean life of all light bulbs of this type. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #301265 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=301265\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A simple random sample of 101 light bulbs had a mean life of 576 hours with a standard devation of 34 hours. <BR>\n" );
document.write( "Construct a 90 percent confidence interval for the mean life of all light bulbs of this type.<BR>\n" );
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document.write( "x-bar = 576<BR>\n" );
document.write( "ME = zs/sqrt(101) = 1.645*34/sqrt(101) = 5.5652<BR>\n" );
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document.write( "90%CI: 576-5.5652 < u < 576+5.5652<BR>\n" );
document.write( "90%CI: 570.43 < u < 581.57 <BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( " </SPAN>\n" );
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