MATH SOLVE

4 months ago

Q:
# 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

A:

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
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confidence coefficient for 90% is 1.64is this right?