Question

in designing a work - desk, it is found that males have sitting knee heights with a mean of 20.2 in. and a standard deviation of 2.4 in. (based on data from the department of transportation). use the range rule of thumb to identify (a) the values that are significantly low, (b) the values that are significantly high, and (c) the values that are neither significantly low nor significantly high.
a. what heights are significantly low? select the correct answer below and fill in the answer box(es) to complete your choice. (type integers or decimals. do not round.)
a. heights that are greater than 15.4 in. and less than 25 in.
b. heights that are greater than 25 in.
c. heights that are less than 15.4 in.

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 less, where $\mu$ is the mean and $\sigma$ is the standard deviation.

Step2: Identify the values of $\mu$ and $\sigma$

Given $\mu = 20.2$ in and $\sigma=2.4$ in.

Step3: Calculate the significant low value

$\mu - 2\sigma=20.2-2\times2.4=20.2 - 4.8 = 15.4$ in. So, values that are significantly low are those less than 15.4 in.

Answer:

C. Heights that are less than 15.4 in.