A stationary store wants to estimate the mean retail value of greeting cards that it has in inventory A random sample of 100 greeting cards. a mean value of 2.55 and standard deviation of 0.44
A. Assuming a normal distribution, construct a 95% confidence interval estimate for the mean value of all greeting cards in the store inventory
B. Suppose there are 2500 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 the inventory
(A) We are given that n=100, xbar = 2.55, sd=0.44 and level=0.95
Standard Error, SE = sd/sqrt(n)=0.44 /√100 = 0.044
z- score = 1.96 from standard normal table ...
The solution gives detailed steps on calculating confidence interval for population mean. All the formula and calcuations are shown and explained.