Question:

10 Honda Civic owners and 12 Toyota Corolla owners were randomly selected, and asked about their cars gas mileage. Yielded the following:

Honda - 28.5, 31.0, 29.6, 26.8, 36.2, 32.4, 30.8, 27.4, 26.6, 29.7.

Toyota - 31.2, 24.8, 28.5, 27.1, 34.9, 26.1, 25.7, 28.8, 29.6, 19.8, 35.0, 26.6.

Assuming that the standard deviations of mph are equal.

A) Find a 99% CI for the difference of their means of mpg.

B) Test the claim that Honda's have better mph with level 0.05.

I'm not just looking for answers however solutions (step by step) to the problems in which I can apply and use for future similar problems. The textbook I am using doesn't quite clearly explain how to set this up and solve.

Thanks in advance! I really appreciate the assistance!