Answer:
77
Step-by-step explanation:
Firstly, we need to calculate the total score of the junior students and the total score of the senior students.
The total score of the junior students is 35 * 80 = 2,800
The total score of the senior students is 15 * 70 = 1050
The total score is thus 2,800 + 1,050 = 3,850
The average score of the 50 students is thus 3,850/50 which equals 77
