document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1191056>Question 1191056</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A researcher studying frogs is investigating the distance that a certain species of frog can jump. The jump-lengths are normally distributed with a mean of 90 inches and a standard deviation of 12 inches.\r<BR>\n" );
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document.write( "Use the Empirical Rule to answer the following questions.\r<BR>\n" );
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document.write( "a) What percent of frog-jumps of this species are less than 78 inches?<BR>\n" );
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document.write( "b) What jump-lengths represent the middle 95% of frog jumps of this species?<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 #822887 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=822887\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> z=(x-mean)/sd<BR>\n" );
document.write( "so a is asking what percent are more than 1 sd less than the mean.  This is 16%, since 32% probability is more than 1 sd from the mean in both directions, and we only want half of that.<BR>\n" );
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document.write( "The middle 95% of jumps are within + and - 2 sd s of the mean<BR>\n" );
document.write( "This is 66 inches from the low end (90-2*12) and 114 inches from the top end (90+2*12) </SPAN>\n" );
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