document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=390610>Question 390610</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A biology class did a survey of an open field for the number of visible insects per square ft. of ground. The results were normally distributed. The mean was 28 insects and the standard deviation was 5.  What values are 1 standard deviation from the mean? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #277231 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=277231\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Use the z-score formula:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=z+=+%28X+-+mu%29%2Fsigma ALIGN=MIDDLE  ALT=\"z+=+%28X+-+mu%29%2Fsigma\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  Hence we want \r<BR>\n" );
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document.write( "+/-<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1+=+%28X+-+28%29%2F5 ALIGN=MIDDLE  ALT=\"1+=+%28X+-+28%29%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" >, or +/-5 = X - 28, or X = 23, 33.<BR>\n" );
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