Question 905928:  The verbal part of the Graduate Record Exam (GRE) has a mean of 500 and a standard deviation of 100. Use the normal distribution to answer the following questions:
 
a. If you wanted to select only students at or above the 90th percentile, what verbal GRE score would you use as a cutoff score? 
b. What verbal GRE score corresponds to a percentile rank of 15%?  
c. What’s the percentile rank of a GRE score of 628?  
 
 Answer by ewatrrr(24785)      (Show Source): 
You can  put this solution on YOUR website! a. z = invNorm(.90) = (X-500)/100 
100invNorm(.90) + 500 = X, score would you use as a cutoff score 
b.  
100invNorm(.15) + 500 = X, verbal GRE score corresponds to a percentile rank of 15% 
z = (628-500)/100 = 128/100 = 1.28 
normalcdf(-100, 1.28) 
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