Question 854003
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Hi,
area under a normal curve to the right of z=2.04 = 1 - NORMSDIST(2.04)
                                                 = 1 - .9793 = .0207  Or 2.07%
For the normal distribution: 
one  standard deviation from the mean accounts for about 68.2% of the set 
<u>two standard deviations</u> from the mean account for about 95.4% 0r{{{.046/2 = .023}}} 2.3% on either end
and three standard deviations from the mean account for about 99.7%.
Important to Understand z -values as they relate to the Standard Normal curve:
Below:  z = 0, z = ± 1, z= ±2 , z= ±3 are plotted.  
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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