Probability based on Normal distribution.
The serum cholesterol levels in men aged 18-24 are normally distributed with a mean of 178.1 and a standard deviation of 40.7. Units are mg/100 mL, and the data are based on the National Health Survey.
a. If one man aged 18-24 is randomly selected, find out the possibility that his serum cholesterol level is greater than 220.
b. If one man aged 18-24 is randomly selected, find out the likelihood that his serum cholesterol level is between 165 and 200.