Posted by roy on Monday, September 23, 2013 at 9:10pm.
suppose that grade point averages of undergraduate students at one university have a bell shaped distribution with a mean of 2.55 and a standard deviation of 0.43. Using the empirical rule, what percentage of students have grade point averages that are between 1.26 and 3.84

statistics  PsyDAG, Wednesday, September 25, 2013 at 5:24pm
Z = (scoremean)/SD
Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability between the two Z scores.