①班级及格人数＝50-2＝48及格率＝及格人数÷班级数人数×100%＝48÷50×100%＝96%②及格率＝100％－不及格率不及格率＝不及格人数÷班级总人数×100％＝2÷50×100％＝4％及格率＝100％－4％＝96%
