document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1171710>Question 1171710</A>: <I><SPAN STYLE=\"word-break: break-all;\"> suppose we wish to estimate the average yield of a chemical plant. the daily yield is known to vary with a standard deviation of 21 tons. the yield recorded for 50 days produced a mean of 871 tons. find a 90% confidence interval for the mean daily yield of chemical produced </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #796618 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=796618\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> half-interval is z(0.95)*sigma/sqrt(n(<BR>\n" );
document.write( "=1.645*21/sqrt(50)=4.89<BR>\n" );
document.write( "90%CI is (866.11, 875.89) units tons </SPAN>\n" );
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