SOLUTION: A typical adult has an average IQ score of 105, with a standard deviation of 20. If 20 randomly selected adults are given an IQ test, what is the probability that the sample mean s

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Question 1204455: A typical adult has an average IQ score of 105, with a standard deviation of 20. If 20 randomly selected adults are given an IQ test, what is the probability that the sample mean scores will be between 87, and 125 points? Round your answer to five decimal points.
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

P%2885+%3C+xbar+%3C+125%29
transform above range to N(0,1) by computing z-scores:





P%28-4.47+%3C+z+%3C+4.47%29+=0.99999