Assume that adults have IQ scores that are normally distributed with a mean of 104.6 and a standard deviation of 21.1. Find the probability that a randomly selected adult has an $I Q$ greater than 141.1. (Hint: Draw a graph.)
The probability that a randomly selected adult from this group has an IQ greater than 141.1 is
(Round to four decimal places as needed.)

Answer

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Answer

\boxed{4.18\%}

Steps

Step 1 ：Calculate the z-score: z = $\frac{X - \mu}{\sigma}$ = $\frac{141.1 - 104.6}{21.1}$ = 1.73

Step 2 ：Find the probability using a standard normal distribution table or a calculator: P(Z > 1.73) = 0.0418

Step 3 ：\boxed{4.18\%}