document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=632893>Question 632893</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The standard deviation of test scores on a certain achievement test is 11. A random sample of  scores on this test had a mean of 70.5. 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( "-what is the lower limit of the 0% confidence interval?<BR>\n" );
document.write( "-what is the upper limit of the 90% confidence interval?\r<BR>\n" );
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document.write( "I am stuck on how to find the standard normal variable. But need a step by step of the entire thing to help me understand. 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 #398528 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=398528\">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 11. A random sample of scores on this test had a mean of 70.5. Based on this sample, find a 90% confidence interval for the true mean of all scores. <BR>\n" );
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document.write( "x-bar = 70.5<BR>\n" );
document.write( "ME = 1.645 </SPAN>\n" );
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