While writing an article on the high cost of college education, a reporter took a random sample of the cost of new textbooks for a semester. The random variable x is the cost of one book. Her sample data can be summarized by the following. (Give your answers correct to two decimal places.)
n = 34, ?x = 3516.6, and ?(x - x)2 = 9890.4
(a) Find the sample mean, x.
b) find the sample standard deviation s
c) find the 95% confidence interval to estimate the true mean textbook cost for the semester based on this sample. Upper limit? Lower limit?