A college student wants to compare the cost of one- and two-bedroom apartments near campus. She collects the following data on monthly rents (in dollars) for a random sample of 30 apartments of each type.

The one-bedroom apartments gave her a sample mean of $531 and a standard deviation of $83. The two-bedroom apartments gave her a sample mean of $609 and a standard deviation of $89.

Construct and interpret a 90% confidence interval for the difference between the mean monthly rents for all one- and two-bedroom apartments near the college campus.

Use one-bedrooms for group 1 and two-bedrooms for group 2.

Question 1. What is the 90% confidence interval?

The confidence interval is ___?____ to ____?____.