1. In an article in the Journal of Management, Morris, Avila and Allen studied innovation by surveying firms to find the number of new products introduced by the firms. A random sample of 100 California based firms are selected. Each firm is asked to report the number of new products introduced last year. The survey found that on average these firms introduced 5.68 products with a standard deviation of 8.70. Compute a 98% confidence interval for the new products introduced last year.
2. The score on the entrance test for a well known law school has a mean score of 200 points and a standard deviation of 50 points. At value should the lowest passing score be set if the school wishes only 2.5% of those taking the entrance test to pass?
3. A trans-oceanic airline conducted a study to determine whether the average weight of baggage checked by a passenger differs significantly from 45 pounds. A random sample of 25 passenger baggages recorded a mean weight of 43.5 pounds with a standard deviation 6 pounds. Can the airline conclude that the mean weight of checked baggage is significantly different from 45 pounds at a 95% level of confidence?