document.write( "Question 853002: I am not understanding how to do this. Could you explain how to do it step by step.I know number 3 was already answered but im not understanding it\r
\n" ); document.write( "\n" ); document.write( "Draw a sketch of the target area and show your calculations for each problem below. Assume that IQ scores are normally distributed with a mean of 100 and a standard deviation of 15. Hint: Use the Empirical Rule (68-95-99.7.)\r
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\n" ); document.write( "\n" ); document.write( "4. What percent of IQs are above 115?
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Algebra.Com's Answer #513818 by ewatrrr(24785)\"\" \"About 
You can put this solution on YOUR website!
 
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document.write( "Hi,
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document.write( "mean of 100 and a standard deviation of 15.
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document.write( "3) below 70 ( 2 SDs to the left)  .05/2 = .025  0r  2.5%
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document.write( "4) above 115 (1 SD to the right)  .32/2 = .16  0r  16%
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document.write( "see graph below
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document.write( "For the normal distribution: 
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document.write( "one  standard deviation from the mean accounts for about 68% of the set ***
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document.write( "two standard deviations from the mean account for about 95% *** (.05% the extreems
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document.write( "and three standard deviations from the mean account for about 99.7%.
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document.write( "Important to Understand z -values as they relate to the Standard Normal curve:
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document.write( "Below:  z = 0, z = ± 1, z= ±2 , z= ±3 are plotted.  
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document.write( "Note: z = 0 (x value the mean) 50% of the area under the curve is to the left and %50 to the right
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