document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=971405>Question 971405</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The mean time taken by all participants to run a road race was found to be 115 minutes with a standard deviation of 20 minutes.<BR>\n" );
document.write( "Using Chebyshev's theorem, find the percentage of runners who ran this road race in 75 to 155 minutes.<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 #594259 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=594259\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Chebyshev's Theorem puts a bound on the percentage between x number of standard deviations. A certain amount of data must fall within 1-[1/(sd)^2], so at least 3/4 of people will be within two standard deviations.  It may be more, and it usually is, but it can not be fewer than 3/4.  \r<BR>\n" );
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document.write( "The data are mean +/- 2 sds or 75 to 155 minutes.  At least 75% of the runners finished in that time interval. </SPAN>\n" );
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