Выполните действия 3+8 5/12,10 6/7 -3,4 2/13+ 5 7 /13,8 7/12 - 4 2/12.

1. 3 + 8 5/12 = (3 + 8) + 5/12 = 11 5/12. 

2. 10 6/7 - 3 = (10 - 3) + 6/7 = 7 6/7. 

3. 4 2/13+ 5 7 /13 = (4 + 5) + (2/13 + 7/13) = 9 + (2 + 7) / 13 = 9 + 9/13 = 9 9/13;

4. 8 7/12 - 4 2/12 = (8 - 4) + (7/12 - 2/12) = 4 + (7 - 2) / 12 = 4 + 5/12 = 4 5/12.