An engineering manager thinks it should take an average of 15.0 hours to properly design the stamping die. A random sample of 24 design records from the 250 dies built last year points out that the average design took 16.6 hours with the standard deviation of 2.22 hours.
Does the sample point out that designers are taking more hours than the manager thinks they should be? Develop the appropriate hypothesis test, determine the P-value, and state your conclusion of the study.