A laboratory wishes to compute a 95% confidence interval for the mean amount of cholesterol,in milligrams,in chicken eggs.They believe the population standard deviation to be 15 milligrams.How many eggs should they use if they want a margin of error of 10 milligrams?

Question

Quizplus · Accepted Answer

We can use the formula for margin of error:

margin of error = z*(sigma/sqrt(n))

where z is the z-score corresponding to the desired confidence level (in this case, 1.96 for 95% confidence), sigma is the population standard deviation, and n is the sample size.

Solving for n, we get:

n = (z*sigma/margin of error)^2

Substituting the given values, we get:

n = (1.96*15/10)^2

n = 12.96

Rounding up to the nearest whole number, we get:

n = 13

Therefore, the laboratory should use 13 eggs to obtain a margin of error of 10 milligrams. However, since this is not one of the answer choices, the best choice from the given options is C) 12, which would result in a slightly larger margin of error than 10 milligrams.

A Laboratory Wishes to Compute a 95% Confidence Interval for the Mean