document.write( "Question 387978: IQ test scores are standardized to produce a normal
\n" ); document.write( "distribution with a mean of u=100 and a standard
\n" ); document.write( "deviation of 0=15. Find the proportion of the population
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\n" ); document.write( "a. Genius or near genius: IQ over 140
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\n" ); document.write( "c. Average or normal intelligence: IQ from 90 to 109 \n" ); document.write( "

Algebra.Com's Answer #274313 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi
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document.write( "*Note:     = 100, = 15
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document.write( "Converting z score to a P decimal using the manner You choose to find percentage
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document.write( "a. Genius or near genius: IQ over 140 
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document.write( "  z > 40/15 = 2.6667 P(z > 2.6667) = .0038  3.8%  of the population
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document.write( "b. Very superior intelligence: IQ from 120 to 140  (z = 20/15 and z = 40/15)
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document.write( " P( 1.333 < z <2.6667) = .0874    8.74% of the population
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document.write( "c. Average or normal intelligence: IQ from 90 to 109 (z = 9/15 and z = -10/15)
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document.write( " ( - .6667 < z < .6) = .4733   47.33% of the population \n" );
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