document.write( "Question 636624: Assume that the average annual salary for a worker in the United States is $38,000 and that the annual salaries for Americans are normally distributed with a standard deviation equal to $7,000. Find the following:
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\n" ); document.write( "(A) What percentage of Americans earn below $25,000?
\n" ); document.write( "(B) What percentage of Americans earn above $46,000? \n" ); document.write( "
Algebra.Com's Answer #401212 by ewatrrr(24785)\"\" \"About 
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document.write( "Hi,
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document.write( "mean = $38,000  and SD = $7000
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document.write( "(A) What percentage of Americans earn below $25,000? P(z < -1) = (100-68.27)/2 = 15.87%
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document.write( "(B) What percentage of Americans earn above $46,000? P(z > 1) = 15.87%
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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 68.27% of the set 
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document.write( "two standard deviations from the mean account for about 95.4%
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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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