Question 1179649
3.37 = 2.51 + 2*.43
3.37 is 2 SD Above or to the right of the mean
percentage of the students have grade point averages that are no more than 3.37:
 .50 + 47.7 = 97.7

one  standard deviation from the mean accounts for about 68.2% of the set 
two standard deviations from the mean account for about 95.4% *******95.4/2 = 47.7
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:
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