document.write( "Question 1180521: For a standard normal distribution, find:
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Algebra.Com's Answer #810214 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "There are two ways, calculator and tables.  I'll explain both.\r\n" );
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document.write( "If you have a TI-83 or TI-84 calculator and are allowed to use it,\r\n" );
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document.write( "press 2nd, then vars, then 2.  If your calculator is newer, you'll see the\r\n" );
document.write( "\"wizard\" screen.  Make it read like this:\r\n" );
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document.write( "       normalcdf\r\n" );
document.write( "lower:-0.78 \r\n" );
document.write( "upper:99999999\r\n" );
document.write( "μ:0\r\n" );
document.write( "σ:1\r\n" );
document.write( "Paste\r\n" );
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document.write( "Scroll down to Paste and press enter.\r\n" );
document.write( "You will read\r\n" );
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document.write( "normalcdf(-0.78,99999999,0,1)\r\n" );
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document.write( "(If your calculator is old, make it read like the previous line):\r\n" );
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document.write( "Then press enter.\r\n" );
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document.write( "You will read\r\n" );
document.write( "0.7823046313 \r\n" );
document.write( "Round to 0.7823\r\n" );
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document.write( "There are two kinds of normal tables in use today.  If your table is like the one on this site:\r\n" );
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document.write( "http://www.z-table.com/\r\n" );
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document.write( "Find -.07 in the leftmost column headed z, then go across to the column\r\n" );
document.write( "headed .08 and read the value .2177.  Since this table reads the area to\r\n" );
document.write( "the left, this value is P(z < -0.78).  But we want P(z > -0.78), so we\r\n" );
document.write( "must subtract from 1 and get 1-.2177 which is 0.7823.\r\n" );
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document.write( "If your table is like the one on this site:\r\n" );
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document.write( " https://www.mathsisfun.com/data/standard-normal-distribution-table.html\r\n" );
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document.write( "Find 0.7 in the leftmost column headed z, then go across to the column\r\n" );
document.write( "headed 0.08 and read the value 0.2823. Since this table reads area to the\r\n" );
document.write( "right of the middle, this value is P(0.5 < z < 0.78).  By symmetry of the\r\n" );
document.write( "normal curve, that is the same as P(-0.78 < z < 0.5).  But we want \r\n" );
document.write( "P(z > -0.78), so we must add 0.5 which is P(z > 0.5).  We get 0.5+0.2823\r\n" );
document.write( "and get 0.7823.\r\n" );
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document.write( "Regardless of how you get it, the answer is 0.7823.\r\n" );
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document.write( "Edwin

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