Question

provide an appropriate response. use the standard normal table to find the probability. iq test scores are normally distributed with a mean of 100 and a standard deviation of 15. an individuals iq score found to be 120. find the z - score corresponding to this value.

a. 0.67
b. 1.33
c. -1.33
d. -0.67

Explanation:

Step1: Recall z - score formula

The z - score formula is $z=\frac{x-\mu}{\sigma}$, where $x$ is the value from the data set, $\mu$ is the mean, and $\sigma$ is the standard deviation.

Step2: Identify values

We are given that $\mu = 100$, $\sigma=15$, and $x = 120$.

Step3: Substitute values into formula

$z=\frac{120 - 100}{15}=\frac{20}{15}=\frac{4}{3}\approx1.33$

Answer:

B. 1.33