document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1169217>Question 1169217</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A clinical trial was conducted to test the effectiveness of a drug for treating insomnia in older subjects. Before​ treatment, 13 subjects had a mean wake time of 100 min. After​ treatment, the 13 subjects had a mean wake time of 77.5 min and a standard deviation of 23.2 min. Assume that the 13 sample values appear to be from a normally distributed population and construct a 90​% confidence interval estimate of the mean wake time for a population with drug treatments. What does the result suggest about the mean wake time of 100 min before the​ treatment? Does the drug appear to be​ effective?\r<BR>\n" );
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document.write( "Construct the ​90% confidence interval estimate of the mean wake time for a population with the treatment.\r<BR>\n" );
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document.write( "please help. I've tried multiple different ways and all lead to the incorrect answer!<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 #793847 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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/cgi-bin/show-face.mpl?user=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=793847\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The half-interval is t(0.95,df=12)*s/sqrt(13)<BR>\n" );
document.write( "=1.782*23.2/sqrt (13)<BR>\n" );
document.write( "=11.47 Add to and subtract from 77.5 min<BR>\n" );
document.write( "the interval is (66.03, 88.97) min\r<BR>\n" );
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document.write( "Since 100 min Ho is outside the interval, the drug appears to be effective.   </SPAN>\n" );
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