1 1/3 + 9 1/6, 9 1/4+1 5/8
10 5/7 + 1 8/21

Ответ:

10 2/9;

10 6/12;

11 13/28;

Пошаговое объяснение:

1 1/3 + 9 1/6 = (1 + 9) + (1/3 + 1/6) = 10 + 2/9 = 10 2/9

9 1/4 + 1 5/8 = (9 +1) + (1/4 + 5/8) = 10 + 6/12 = 10 6/12

10 5/7 + 1 8/21 = (10 + 1) + (5/7 + 8/21) = 11 + 13/28 = 11 13/28