A maker of a certain brand of low fat cereal bars claims the average saturated fat content is 0.5 grams. To check the claim, a random sample of 9 cereal bars of this brand was drawn, and the sample mean was found to be 0.52. Assume that the population standard deviation is 0.2.
Assume the distribution of the fat content is aproximately normal, what is the sampling distribution of the sample mean?