Question

mr. emmer gave a test in his chemistry class. the scores were normally distributed with a mean of 82 and a standard deviation of 4. a student is randomly chosen. what is the probability that the student scores an 88 or below? use the formula for a z - score $z=\frac{x - mu}{sigma}$ where x is the given value, $mu$ is the mean and $sigma$ is the standard deviation. then refer to the chart on page 11 of the lesson to find the probability.
a..9332
b..8643
c..9918
d..6915

Explanation:

Step1: Calculate the z - score

Given $\mu = 82$, $\sigma=4$, $x = 88$. Using the formula $z=\frac{x - \mu}{\sigma}$, we have $z=\frac{88 - 82}{4}=\frac{6}{4}=1.5$.

Step2: Find the probability

Looking up the z - score of 1.5 in the standard normal distribution table, the probability corresponding to $z = 1.5$ is 0.9332.

Answer:

A. 0.9332