document.write( "Question 1061809: The scores on a test is normally distributed with a mean of 100 and a standard deviation of 11. What is the probability that a score will be between 97 and 125? \n" ); document.write( "

Algebra.Com's Answer #676650 by Edwin McCravy(20060) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "On your TI-83 or TI-84\r\n" );
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document.write( "normalcdf(97,125,100,11), read .595947231, Press ENTER\r\n" );
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document.write( "To find \"normalcdf(\" on your calculator, press 2ND then 2\r\n" );
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document.write( "If your teacher won't allow calculator work, find z-scores\r\n" );
document.write( "for the endpoints:\r\n" );
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document.write( " and \r\n" );
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document.write( "If your table contains negative z values, look up z=-0.27 \r\n" );
document.write( "(the closest you can get to -.2727, and read 0.3936, and \r\n" );
document.write( "look up z=2.27, (the closest you can get to 2.2727 and read \r\n" );
document.write( "0.9884.\r\n" );
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document.write( "Subtract and get 0.9884-0.3936 = 0.5948.\r\n" );
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document.write( "If your table contains only positive z values, look up z=0.27 \r\n" );
document.write( "(the closest you can get to .2727, and read 0.1064, and look \r\n" );
document.write( "up z=2.27, (the closest you can get to 2.2727 and read 0.4884.\r\n" );
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document.write( "Add and get 0.1064+0.4884 = 0.5948.\r\n" );
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document.write( "The calculator value 0.595947231 is more accurate, since we \r\n" );
document.write( "don't have to round off the z-scores when we use the \r\n" );
document.write( "calculator.\r\n" );
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document.write( "[It's a shame that teachers and books still require old-fashioned\r\n" );
document.write( "inaccurate tables when technology is available so freely.]\r\n" );
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document.write( "Edwin

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