document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=438811>Question 438811</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 13 Chevrolet Corvettes were crash tested under a variety of conditions that simulate typical collisions. The mean repair cost for this sample of Corvettes was $16,540. The repair cost standard deviation for this sample was $6,782. Repair Costs for corvettes are believed to have a normal distribution. Construct a 99% confidence interval for the mean repair cost of all Corvettes involved in crashes.\r<BR>\n" );
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document.write( "mean= 16,540<BR>\n" );
document.write( "St dev= 6,782<BR>\n" );
document.write( "n=13\r<BR>\n" );
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document.write( "(2.578)(6,782/sq rt13)= 4849.188005<BR>\n" );
document.write( "The answer is coming out wrong... can you tell me where i have gone wrong? <BR>\n" );
document.write( "Thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #303355 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=303355\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 13 Chevrolet Corvettes were crash tested under a variety of conditions that simulate typical collisions. The mean repair cost for this sample of Corvettes was $16,540. The repair cost standard deviation for this sample was $6,782. Repair Costs for corvettes are believed to have a normal distribution. Construct a 99% confidence interval for the mean repair cost of all Corvettes involved in crashes. <BR>\n" );
document.write( "x-bar =  16,540<BR>\n" );
document.write( "St dev= 6,782<BR>\n" );
document.write( "n=13 <BR>\n" );
document.write( "ME = (2.576)(6,782/sq rt13)= 4845.11<BR>\n" );
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document.write( "You're right.<BR>\n" );
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document.write( "99% CI: 16,540-4845.11 < u < 16540+4845.11<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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