An industrial arts instructor has deisgned a test of mechancical aptitude (MechA) and having investigated its properties, finds that studnets with scores lower than 8 tend to do poorly in the class. Those with scores higher than 12 excell. Admininistering it to a random sample of industrial arts students reveals the following scores: 7, 5 9, 13, 12, 10, 14, 10, 11, 10.
a) What percentage of the distribution will fall in the area of the distribution expected to do poorly?
b) What percentage of teh distribution will fall in the area of the distribution expected to excell?
c) A score of 12 occurs at what percentile?