document.write( "Question 860221: In a certain distribution, the mean is 40 with a standard deviation of 2. At least what fraction of numbers are between the following pair of numbers?
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Algebra.Com's Answer #518236 by ewatrrr(24785)\"\" \"About 
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document.write( "Hi,
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document.write( "mean is 40 with a standard deviation of 2
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document.write( "P(36 < x <44) = P(-2 < z < 2)   at least 95/100 = 19/20 of numbers are between 36 & 44
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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 68.2% 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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