The Quality Assurance Department for Cola, Inc., maintains records regarding the amount of cola in its Jumbo bottle. The actual amount of cola in each bottle is critical, but varies a small amount from one bottle to the next. Cola, Inc., does not wish to underfill the bottles. On the other hand, it cannot overfill each bottle. Its records indicate that the amount of cola follows the normal probability distribution. The mean amount per bottle is 31.2 ounces and the population standard deviation is 0.4 ounces. If 16 bottles are randomly selected from the filling line. The mean amount of cola contained in the bottles is 31.38 ounces.

Question

Calculate . (i) Using Standard Normal Distribution Table (ii) Using a direct Excel formula to verify your answer