document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1180589>Question 1180589</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The length of a certain kind of Colorado brook trout is normally distributed with a mean of 13.1 inches and a standard deviation of 1.5 inches.\r<BR>\n" );
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document.write( "What minimum size limit should the Department of Natural Resources set if it wishes to allow people to keep 80 percent of the trout they catch? <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #810318 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=810318\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 20th percentile is a z of -0.8416<BR>\n" );
document.write( "z=(x-mean)/sd<BR>\n" );
document.write( "-0.8416=(x-13.1)/1.5<BR>\n" );
document.write( "-1.26=x-13.1<BR>\n" );
document.write( "x=11.84 inches.<BR>\n" );
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