A laboratory tested 85 chicken eggs and found that the mean amount of cholesterol was 190 milligrams. Assume that the sample standard deviation is 11.7 milligrams. Construct a 95% confidence interval for the true mean cholesterol content, μ, of all such eggs. State your conclusion in a statistical sentence.

Respuesta :

Answer:   [tex](182.356,\ 197.644)[/tex]

Step-by-step explanation:

Given : Significance level : [tex]\alpha:1-0.95=0.05[/tex]

Sample size : n=85

Critical value : [tex]z_{\alpha/2}=1.96[/tex]

Sample mean : [tex]\overline{x}=190[/tex]

Standard deviation : [tex]\sigma=11.7[/tex]

The confidence interval for population mean is given by :-

[tex]\overline{x}\pm z_{\alpha/2}\dfrac{\sigma}{\sqrt{n}}\\\\=190\pm(1.96)\dfrac{11.7}{\sqrt{9}}\\\\=190\pm7.644\\\\=(190-7.644,\ 190+7.644)=(182.356,\ 197.644)[/tex]

Thus, the 95% confidence interval for the true mean cholesterol content, μ, of all such eggs = [tex](182.356,\ 197.644)[/tex]

Hence, we conclude that the true population mean of amount of cholesterol lies between 182.356 and 197.644.