document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1193228>Question 1193228</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In a hospital study, the mean noise level in the 171 ward areas was 58.0 decibels, and the Population standard deviation is 4.8. Find the 90% confidence interval of the true mean.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #825292 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=825292\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 90% half-interval is z*sigma/sqrt(n)<BR>\n" );
document.write( "=1.645*4.8/sqrt(171)<BR>\n" );
document.write( "=0.60<BR>\n" );
document.write( "(57.4, 58.6) decibels </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );