In: Statistics and Probability
The average annual cost (including tuition, room, board, books, and fees) to attend a public college takes nearly a third of the annual income of a typical family with college-age children.† At private colleges, the average annual cost is equal to about 60% of the typical family's income. The following random samples show the annual cost of attending private and public colleges. Data are in thousands of dollars.
51.8 | 43.2 | 46.0 | 34.3 | 44.0 |
30.6 | 45.8 | 36.8 | 51.5 | 42.0 |
20.3 | 22.0 | 28.2 | 15.6 | 24.1 | 28.5 |
22.8 | 25.8 | 18.5 | 25.6 | 14.4 | 21.8 |
a) Compute the sample mean (in thousand dollars) and sample standard deviation (in thousand dollars) for private colleges. (Round the standard deviation to two decimal places.)
sample mean = ____
sample standard deviation = ____
b) What is the point estimate (in thousand dollars) of the difference between the two population means? (Use Private − Public.) =______
Interpret this value in terms of the annual cost (in dollars) of attending private and public colleges. We estimate that the mean annual cost to attend private colleges is _____ more than the mean annual cost to attend public college