document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1161496>Question 1161496</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The manager of a warehouse store wants to estimate the average number of laser printer toner cartridges sold each day. A random sample of 37 days is selected and the sample mean is 115. The population standard deviation is estimated to be 9.8. Test the claim, using a 95% confidence interval for the mean, that the average number of laser printer toner cartridges sold each day is 110.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #785201 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=785201\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> half interval is z(0.975)*sigma/sqrt(n)<BR>\n" );
document.write( "=1.96*9.8/sqrt(37)<BR>\n" );
document.write( "=3.16<BR>\n" );
document.write( "so the interval is (111.84, 118.16), adding and subtracting to and from the mean.<BR>\n" );
document.write( "Because 110 is not in the interval, one rejects the claim.  If 110 were in the claim, then we would be 95% confident that the true number could be 110, which is claimed.\r<BR>\n" );
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