640  Average
2

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Class A - 12 students with the score 50%.
Class B - 8 students with the score 80%.
What is the total average score?



Class A - 7 students with the score 90%.
Class B - 3 students with the score 80%.
What is the total average score?



Class A - 3 students with the score 70%.
Class B - 7 students with the score 90%.
What is the total average score?



Class A - 17 students with the score 60%.
Class B - 3 students with the score 60%.
What is the total average score?



Class A - 3 students with the score 90%.
Class B - 7 students with the score 90%.
What is the total average score?

Class A - 7 students with the score 50%.
Class B - 3 students with the score 70%.
What is the total average score?



Class A - 13 students with the score 70%.
Class B - 7 students with the score 40%.
What is the total average score?



12 명인 남학생반의 평균점수는 80 점이고,
8 명인 여학생반의 평균점수는 50 점일때,
두 반 전체 평균 점수는 얼마인가?



Class A - 4 students with the score 90%.
Class B - 6 students with the score 50%.
What is the total average score?



Class A - 5 students with the score 40%.
Class B - 5 students with the score 60%.
What is the total average score?

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