SOLUTION: Over what grade should we find the 5 best students of 37 in a test with an average of 81 and standard deviation of 7?

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Question 847575: Over what grade should we find the 5 best students of 37 in a test with an average of 81 and standard deviation of 7?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

m= 81, sd = 7, n = 37, top 5   0r top 13.5 percentile

Normsinv(.135) =  z = 1.102 = (x - 81)/7

    1.102 = (x - 81)/7

     7.7 + 81 = 88.7   Over an 89 test score