Private colleges and universities rely on money contributed by individuals and corporations for their operating expenses. Much of this money is invested in a fund called an endowment, and the college...

Private colleges and universities rely on money contributed by individuals and corporations for their operating expenses. Much of this money is invested in a fund called an endowment, and the college spends only the interest earned by the fund. A recent survey of eight private colleges in the United States resulted in the following summary statistics for their endowments: x-bar = 180.975 and s = 143.042. Calculate a 99% confidence interval for the mean endowment of all private colleges in the United States.