Jos "Pancho" Lorenzo is a businessman and owner of the Texaco gas stations. Pancho is interested in estimating the number of gallons of gasoline that were sold. He assumes that the number of gallons of fuel sold follows a normal distribution with a standard deviation of 2.30 gallons. According to the records, he selects a random sample of 60 sales in the month of April and finds that the mean number of gallons sold is 8.60.

Answer:

a. What is the point estimator of the population mean?

b. Set the 99% confidence interval for the population mean.

c. Interpret the result of the calculation performed in b.