Is the nutrition information on commercially produced food accurate? In one study, researchers sampled 13 packages of a certain frozen reduced-calorie chicken entree with a reported calorie content of 252 calories per package. The mean calorie count of the sampled entrees was 306 with a sample standard deviation of 51 calories.59
(a) Compute a 95% confidence interval for the population mean calorie content of the frozen entree.
(b) Based on this interval computed in part (a), what do you think about the reported calorie content for this entree?
(c) Manufacturers are punished if they provide less food than advertised. How does this fact relate to your results in (a) and (b)?