SOLUTION: An IQ test has a mean of 100 and a standard deviation of 15. Assume a normal distribution. Find the probability. 1. What is the probability that someone scores more than 12

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Question 1152772: An IQ test has a mean of 100 and a standard deviation of 15. Assume a normal distribution. Find the probability.
1. What is the probability that someone scores more than 125 points?
Answer by VFBundy(438) About Me  (Show Source):
You can put this solution on YOUR website!
z-score = %28IQ+-+mean%29%2FSD = %28125+-+100%29%2F15 = 25/15 = 1.67

Look up 1.67 on a z-table. The value is 0.9525. This is the probability someone scores LESS than 125. So, the probability someone scores MORE than 125 is the inverse, or 0.0475.