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 4 points with 99 % confidence assuming s equals 12.2 based on earlier​ studies? Suppose the doctor would be content with 90 % confidence. How does the decrease in confidence affect the sample size​ required?LOADING... Click the icon to view a partial table of critical values.A​ 99% confidence level requires nothing subjects. ​(Round up to the nearest​ subject.)

Accepted Solution

Answer:  confidence coefficient for 90% is 1.64Step-by-step explanation:confidence coefficient for 99% is 2.58   2.58 * 19.4/sqrt(n) = 0.04  2.598*19.4/0.04 = sqrt(n)   ( 2.598*19.4/0.04)^2  = n  1587676    ---------------------  confidence coefficient for 90% is 1.64is this right?