Question

use the range - rule of thumb to identify the values that are significantly low, the values that are significantly high, and the values that are neither significantly low nor significantly high. a test is used to assess readiness for college. in a recent year, the mean test score was 22.6 and the standard deviation was 5.2. identify the test scores that are significantly low or significantly high. what test scores are significantly low? select the correct answer below and fill in the answer box(es) to complete your choice.

a. test scores that are less than

b. test scores that are between

c. test scores that are greater than

(round to one decimal place as needed)

Explanation:

Step1: Recall range - rule - of - thumb for significant values

According to the range - rule - of - thumb, significant low values are $\mu - 2\sigma$ or lower, and significant high values are $\mu+ 2\sigma$ or higher, where $\mu$ is the mean and $\sigma$ is the standard deviation.

Step2: Calculate the significant low value

Given $\mu = 22.6$ and $\sigma = 5.2$. The formula for the significant low value is $x=\mu - 2\sigma$. Substitute the values: $x=22.6-2\times5.2$. First, calculate $2\times5.2 = 10.4$. Then, $22.6−10.4 = 12.2$.

Answer:

A. Test scores that are less than 12.2