Question: A stationery store wants to estimate the mean retail value of greeting cards that it has in its inventory. A random sample of 100 greeting cards indicates a mean value of $2.55 and a standard deviation of $0.44.
a. Assuming a normal distribution, construct a 95% confidence interval estimate of the mean value of all greeting cards in the store s inventory.
b. Suppose there were 2,500 greeting cards in the store s inventory. How are the results in (a) useful in assisting the store owner to estimate the total value of her inventory?