We draw a simple random sample of 30 retail businesses in a population of 1250

retail businesses.We retain the following information on each of them:

Number of employees;

Payroll (the sum of salaries paid to employees).

Determine the upper bound of a 95% confidence interval for the wage bill

average per trade

Number of employees Payroll (in thousands of $) Sum 1531 3, 342 Corrected standard deviation 1.99335 49.6553 Covarianae 98.16%