A laboratory tested 90 chicken eggs and found that the mean amount of cholesterol was 230 milligrams with italic sigma space equal space 16.0 milligrams. Construct a 95 percent confidence interval for the true mean cholesterol content, μ, of all such eggs.

Given:

Sample size, n = 90

Expected mean, μ = 230 mg

Standard deviation, σ = 16 mg

At 95% confidence interval, the true mean will lie in the interval

(μ + 1.96 (σ/√n), μ - 1.96 (σ/√n)

= (230 + (1.96*16) / √ (90), 230 - (1.96*16) / √ (90))

= (230 - 3.306, 230 - 3.306)

= (233.3, 226.7) to nearest tenth

Answer:

The 95% confidence interval for the true mean is (233.3, 226.7)