document.write( "Question 1033517: The numbers of pages in the books in a library follow a
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Algebra.Com's Answer #648151 by Edwin McCravy(20056) $\"\"$ $\"About$

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document.write( "In a normally distributed population, by the \r\n" );
document.write( "\"empirical rule\",\r\n" );
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document.write( "1.  68% of the distribution lies within one standard\r\n" );
document.write( "    deviation of the mean. \r\n" );
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document.write( "2.  95% of the distribution lies within two standard \r\n" );
document.write( "    deviations of the mean. \r\n" );
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document.write( "3.  99.7% of the distribution lies within three standard \r\n" );
document.write( "    deviations of the mean.\r\n" );
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document.write( "Therefore, in that library, we can conclude that: \r\n" );
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document.write( "1.  68% of the books have between 180-30 or 150 and \r\n" );
document.write( "    180+30 or 210 pages.\r\n" );
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document.write( "2.  95% of the books have between 180-2*30 or 180-60 \r\n" );
document.write( "    or 120 and 180+2*30 180+60 or 240 pages.\r\n" );
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document.write( "3.  99.7% of the books have between 180-3*30 or 180-90 \r\n" );
document.write( "    or 90 and 180+90 or 270 pages.\r\n" );
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document.write( "Edwin

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