(T-test Assignment)

NCP manufactures printers and fax machines at plants located in Atlanta, Dallas, and Seattle. To measure how much employees at these plants know about quality management, a random sample of six employees was selected from each plant and the employees selected were given a quality awareness examination. The examination scores for these 18 employees are shown in below Table. Managers want to use these data to test the hypothesis that the mean examination score is the same for all three plants.

Examination Scores For 18 Employees Plant 1 Plant 2 Plant 3 Atlanta Dallas Seattle 85 71 59 75 75 64 82 73 62 76 74 69 71 69 75 85 82 67