Question

The service manager of a car dealer wants to determine if owners of new cars (A) tune up their cars more frequently than owners of older cars (B). From his records he takes a random sample of ten new cars and ten older cars and determines the number of times the cars were tuned up in the last 12 months. Assume the population variances are equal. State the null and alternative hypotheses to determine if new car owners tune up their cars more frequently than older car owners.

Answer 1

Null hypothesis: ∪ₐ = ∪ₓ

Alternative hypothesis: ∪ₐ ≠ ∪ₓ

Explanation:

Null hypothesis: ∪ₐ = ∪ₓ

Alternative hypothesis: ∪ₐ ≠ ∪ₓ

where ∪ₐ represents mean of sample of new cars and ∪ₓ represents mean of sample of older cars.

Using a difference in means t test will help determine if new owners tune up their cars more frequently than older car owners.