The College Board reported that 60.3% of all students who took the 2016 AP Statistics exam earned scores of 3 or higher. One teacher wondered if the performance of her school was better. She believed that year’s students to be typical of those who will take AP Stats at that school and was pleased when 34 of her 54 students achieved scores of 3 or better.
a) How many standard deviations above the national rate did her students score? Does that seem like a lot?
b) Can she claim that her school is better?