document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=69160>Question 69160</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0131483161/algebrahomeworkh>Elementary Statistics</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> A placement exam for entrance into a math class yields a mean of 80 and a standard deviation of 10. The distribution of the scores is roughly bell-shaped. Use the Empirical Rule to find the percentage of scores that lie between 60 and 80.<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 #49226 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=49226\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A placement exam for entrance into a math class yields a mean of 80 and a standard deviation of 10. The distribution of the scores is roughly bell-shaped. Use the Empirical Rule to find the percentage of scores that lie between 60 and 80.<BR>\n" );
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document.write( "60 is 2 standard deviations below the mean.<BR>\n" );
document.write( "The emperical rule says there is approximately 90% of normally distributed<BR>\n" );
document.write( "data within 2 standard deviations of the mean.  Your interval is half of <BR>\n" );
document.write( "that because it is the data between the mean and two standard deviations<BR>\n" );
document.write( "below the mean.  Your answer is 47.5%.<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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