Could someone please help me to complete the following query ? Also please provide the explanation/formulas for my future reference.
A doctor wants to estimate the mean HDL cholesterol of all 20- to 29-year-old females. How many subjects are needed to estimate the mean HDL cholesterol within 3 points with 99 % confidence assuming is equals 14.9 based on earlier studies? Suppose the doctor would be content with 90 % confidence. How does the decrease in confidence affect the sample size required?
A 99% confidence level requires subjects. (Round up to the nearest subject.)
A 95% confidence level requires subjects. (Round up to the nearest subject.)
Thanks in advance !!