SOLUTION: Given a frequency distribution of 10,000 scores, which approximates the normal curve and has a mean of 120 and a standard deviation of 15, the top 80% had a what raw score or great

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Question 1068945: Given a frequency distribution of 10,000 scores, which approximates the normal curve and has a mean of 120 and a standard deviation of 15, the top 80% had a what raw score or greater?

a)94.34

b)107.4

c)110

d)106

Answer by trsomas23@gmail.com(17) About Me  (Show Source):
You can put this solution on YOUR website!
80% = 0.8
From standard normal table
P(Z > -0.84) = 0.8
Z = (x - mean)/sd
x = Z * sd = mean
When Z = -0.84, then
x = -0.84 * 15 + 120
= 107.4
Answer: (b) 107.4
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