a total of 50 juniors and seniors were given a mathematics test.the 35 juniors attained an average score of 80 while the 15 seniors attained an average of 70.what was the averagescore for all 50 students who took the test? please explain if you can

Answer 1

since the average of the 35 juniors was 80, the total of their scores was 35x80 = 2800

the average of the 15 seniors was 70, so their total was 15x70 = 1050

total sum = 3850, so for the 50 students the average was 3850/50 or 77