During a recent year the average cost of making a car was 58

During a recent year, the average cost of making a car was $58 million. A simple random sample of 15 action movies was taken during that year; the sampled action movies cost a mean of $62.5 million to make, with a sample standard deviation of $9.5 million. Is this evidence that action movies cost more to make, on average, than movies in general?

Solution

Ho: Mu = $58 million

Ha: Mu > $58 million

Test statistic, t = (xbar