Question

= Homework: Chapter 6 Homework Part CQuestion 12, Instructor-Assume that adults have IQ scores that are normally distributed with a mean of u = 100 and a standard deviation o = 20.Find the probability that a rrandomly selected adult has an IQ less than 124.The probability that a randomly selected adult has an IQ less than 124 is(Type an integer or decimal rounded to four decimal places as needed.)

Answer 1

Given

The mean and standard deviation of the given distribution is,

$\begin{gathered} \mu=100 \\ \sigma=20 \end{gathered}$

To find the probability that a randomly selected adult has an IQ less than 124.

Explanation:

It is given that,

The mean and standard deviation of the given distribution is,

$\begin{gathered} \mu=100 \\ \sigma=20 \end{gathered}$

Then, for x=124,

$\begin{gathered} z=\frac{x-\mu}{\sigma} \\ =\frac{124-100}{20} \\ =\frac{24}{20} \\ =\frac{6}{5} \\ =1.2 \end{gathered}$

Then,

$\begin{gathered} P(x<124)=P(z<1.2) \\ =0.3849 \end{gathered}$

Hence, the answer is 0.3849.