A candy maker produces mints that have label weight of 20 grams on each box. Assume that the weight of a box of mints is normally distributed with a standard deviation of 0.4 grams.
(a) Determine the sampling distribution of sample mean weight for a sample of a dozen boxes of mints?
(b) Suppose you bought such a box of mints and it weighed 19.7 grams. What is the probability that a box of mints will weigh as low as 19.7 grams or lower? Would you consider this evidence that the candy maker's claim is incorrect? Explain.
(c) Suppose you bought a dozen boxes of mints and found the average weight to be 19.7 gm. What is the probability that the sample mean of a dozen boxes of mints will weigh as low as 19.7 gram. Would you consider this evidence that the candy maker's claim is incorrect? Explain.