Total cholesterol in children aged 10 to 15 years of age is assumed to follow a normal distribution with a mean of 191 and a standard deviation of 22.4.
a. What proportion of children 10 to 15 years of age have a total cholesterol between 180 and 190?
b. What proportion of children 10 to 15 years of age would be classified as hyperlipidemic assume that hyperlipidemia is defined as cholesterol level over 200?
c. What is the 90th percentile of total cholesterol?