document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=308543>Question 308543</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A random sample of 16 pharmacy customers showed the waiting times below (in minutes)Find a 90 percent confidence interval for u. assuming that the sample is from a normal population\r<BR>\n" );
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document.write( "21 22 22 17 21 17 23 20<BR>\n" );
document.write( "20 24 9 22 16 21 22 21 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #220692 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=220692\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A random sample of 16 pharmacy customers showed the waiting times below (in minutes)Find a 90 percent confidence interval for u. assuming that the sample is from a normal population <BR>\n" );
document.write( "21 22 22 17 21 17 23 20<BR>\n" );
document.write( "20 24 9 22 16 21 22 21<BR>\n" );
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document.write( "Find the sample mean and the sample std.<BR>\n" );
document.write( "x-bar = 19.73<BR>\n" );
document.write( "s = 3.7315<BR>\n" );
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document.write( "E = 1.645*3.7315/sqrt(16) = 1.5344<BR>\n" );
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document.write( "90% CI: 19.73-1.5344 < u < 19.73+1.5344<BR>\n" );
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document.write( "cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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