A stationery store wants to estimate the total retail value of the 300 greeting cards that it has in its inven

A stationery store wants to estimate the total retail value of the 300 greeting cards that it has in its inventory. What are the upper and lower limits of the 95% confidence interval estimate of the population total value of all greeting cards that are in inventory if a random sample of 20 greeting cards indicates an average value of $1.67 and a standard deviation of $0.32

A stationery store wants to estimate the total retail value of the 300 greeting cards that it has in its inven
95% confidence is close to +/-2 sigmas.





So 95% of the sample ranges between $1.03 and $2.31.





Multiply them by 300, and with 95% confidence, the total retail value is between $309 and $693.
Reply:95% confidence interval is roughly +/- two sigma.





So, $1.03 to $2.31 per card.





You can do the math from there. :-)