a) An internal report issued by the marketing manager for a national oil-change franchise indicated that the mean number of miles between oil changes for franchise customers is at least 3,600. One Texas franchise owner conducted a study to determine whether the marketing manager’s statement was accurate for his franchise’s customers. He selected a simple random sample of 10 customers and determined the number of miles each had driven the car between oil change. He obtained the following sample data:
3,655 4,204 1,946 2,789 3,555
3,734 3,208 3,311 3,920 3,902
i. Calculate mean and standard deviation for the above data.