Question

Suppose that the mean cranial capacity for men is 1180 cc (cubic centimeters) and that the standard deviation is 300 cc. Assuming that men's cranial capacities are normally distributed, complete the following statements. (a) Approximately ___ of men have cranial capacities between 880 cc and 1480 cc(b) Approximately 95% of men have cranial capacities between ___ cc and ___ cc.

Answer 1

Step 1

Given;

$\begin{gathered} mean=\mu=1180 \\ Standard\text{ Deviation=}\sigma=300 \end{gathered}$

Step 2

Using the empirical rule;

[tex]P(\mu-\sigmaA) Hence, approximately 68% of men have cranial capacities between 880cc and 1480cc.

[tex]\begin{gathered} P(\mu-2\sigmaB) Hence approximately 95% of men have cranial capacities between 580cc and 1780cc.