doctor wants to estimate the mean HDL cholesterol of all20- to29-year-old females. How many subjects are needed to estimate the mean HDL cholesterol within 2

2 points with 99 %

99% confidence assuming s equals 17.5

s=17.5 based on earlierstudies? Suppose the doctor would be content with 90 %

90% confidence. How does the decrease in confidence affect the sample sizerequired?

A 90 %

90% confidence level requires____subjects???

plase explain