document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=348451>Question 348451</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The standard deviation of test scores on a certain achievement test is 10.5 . A random sample of scores on this test had a mean of 72.8. Based on this sample, find a 90% confidence interval for the true mean of all scores. 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" );
document.write( "The lower limit of 90% confidence interval = <BR>\n" );
document.write( "The upper limit of 90% 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 #249101 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=249101\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  The standard deviation of test scores on a certain achievement test is 10.5 . A random sample of scores on this test had a mean of 72.8. Based on this sample, find a 90% confidence interval for the true mean of all scores. Then complete the table below.<BR>\n" );
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document.write( "x-bar = 72.8<BR>\n" );
document.write( "E = (invNorm(0.95))*10.5 = 1.645*10.5 = 17.27<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.<BR>\n" );
document.write( "The lower limit of 90% confidence interval = 72-17.27 <BR>\n" );
document.write( "The upper limit of 90% confidence interval = 72+17.27<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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