document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1182874>Question 1182874</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The effectiveness of a blood-pressure drug is being investigated.<BR>\n" );
document.write( "An experimenter finds that, on average, the reduction in systolic blood pressure is 55.8 for a sample of size 29 and a standard deviation 7.9.<BR>\n" );
document.write( "Estimate how much the drug will lower a typical patient's systolic blood pressure (using a 90% confidence level).<BR>\n" );
document.write( "Assume that the data is from a normally distributed population.\r<BR>\n" );
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document.write( "Enter answer as a tri-linear inequality accurate to 3 decimal places. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #813203 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=813203\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> half-interval for 90% confidence is t(df=28, 0.95)=1.701*s/sqrt(n)<BR>\n" );
document.write( "=1.701*7.9/sqrt(29)<BR>\n" );
document.write( "=2.495  (decimal blood pressures aren't used, if done without a catheter in the artery, have at least 2-3 mm  error in precision or repeatability, and the final answer should be an integer; that is the physician in me speaking).<BR>\n" );
document.write( "(53.305, 58.295) depression of BP in units mm Hg.<BR>\n" );
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