A customer in the wholesale garment trade is often entitled to a discount for a cash payment for goods. The amount of discount varies by vendor a sample of 150 items selected from a population of 4000...

A customer in the wholesale garment trade is often entitled to a discount for a cash payment for goods. The amount of discount varies by vendor a sample of 150 items selected from a population of 4000 invoices at the end of a periopd of time revealed that in 13 cases the customer failed to take the discount to which he or she was entitles the amounts ( in dollar) of the 13 discount that were not taken were as follow:

6.45, 15.32, 97.36, 230.63, 104.18, 84.92, 132.76, 66.12, 26.55, 129.43, 88.32, 47.81, 89.01

Construct a 99% confidence interval estimate of the population total amount of discount not taken.