AP Stats 2017. The College Board reported that 53.8% of all students who took the 2017 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 30 of her 54 students achieved scores of 3 or better.

a) How many standard errors above the national rate did her students score? Does that seem like a lot? Explain.

b) Can she claim that her school is better? Explain.