The owner of a service station wants to determine if owners of new cars (two years old or less) change their cars’ oil more frequently than owners of older cars (more than two years old). From his records he takes a random sample of 10 new cars and 10 older cars and determines the number of times the oil was changed in the last 12 months. The data are given below. (A) State both the null and alternative hypotheses. (B) Is this a right-tailed test, a left-tailed test, or a two-tailed test? (C) Do these data allow the service station owner to infer at the 5% significance level that new car owners change their cars’ oil more frequently than older car owners? (In other words, do we reject the null or not reject the null in favor of the alternative?) Bold the cell that you used to make this decision. Also format this cell as a percentage with two digits after the decimal point.  

New Car Owners 6 3 3 3 4 3 6 5 5 4

Old Cars Owners 4 2 1 2 3 2 2 3 2 1