Answer:
79
Explanation:
Number of accounting majors = 15
Average grade = 90
Meaning that the total grade of accounting majors = 15*90 = 1350
Number of marketing majors = 25
Average grade = 70
Meaning that the total grade of marketing majors = 25*70 = 1750
Number of finance majors = 10
Average grade = 85
Meaning that the total grade of finance majors = 10*85 = 850
This means that total number of student taking the exam = 15 + 25 + 10 = 50
Total grade of all students = 1350 + 1750 + 850 = 3950
Weighted mean grade = Total grade of all students/total number of students
= 3950/50 = 79