SOLUTION: IQ as measured by the Wechsler Adult Intelligence Test, is scaled so that the mean in the population is 100 with a standard deviation of 15. What is the probability of randomly sam

Question 581578: IQ as measured by the Wechsler Adult Intelligence Test, is scaled so that the mean in the population is 100 with a standard deviation of 15. What is the probability of randomly sampling a member out of this population who has an IQ of 120 or greater?
What is the probability of randomly sampling a set of 5 people out of this population who have a mean IQ of 120 or greater.
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
IQ as measured by the Wechsler Adult Intelligence Test, is scaled so that the mean in the population is 100 with a standard deviation of 15. What is the probability of randomly sampling a member out of this population who has an IQ of 120 or greater?
What is the probability of randomly sampling a set of 5 people out of this population who have a mean IQ of 120 or greater.
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z(120) = (120-100)/15 = 20/15 = 4/3
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P(x > 120) = P(z > 4/3) = normalcdf(4/3,100) = 0.0912
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Chers,
Stan H.
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