Suppose math is X, English is Y, the average score is Z, X=z- 12 (you didn't write it, I understand that math is less than the average score 12, if it is more, Z+ 12), and Y = Z-4. That is 78+82+80+60+x+y = z. Cancel 300=4Z+ 16. Get Z=7 1, X=59, Y=67. That is, math 59 and foreign language 67. The average score is 7 1 (again, this is a math problem in the third grade of primary school)