Пошаговое объяснение:

1) 2 1/6 + 2 5/12= 2 2/12 +2 5/12= 4 2+5/12=4 7/12

2) 9 3/8 + 7 5/6 = 16 8/24 +20/24 = 16 28/ 24 =17 4/24

3)5 1/10 +8 3/8 = 5 8/80 +8 30/80=13 38/80

4)6 2/15 + 42 18/25 = 6 10/75 + 42 54/75= 48 64/75

5)5 3/18 + 18 1/27 = 5 9/54 + 18 2/54 = 23 11/54

6) 9 3/20 + 7 4/15 = 9 9/60 + 7 16/60 = 16 25/60=16 5/12

7)2 19/44 + 5 52/66 = 2 57/132 + 5 104/132 = 7 161/132

8) 38 21/26 + 14 34/39 = 38 63/78 + 14 68/78 = 52 128/78 = 53 50/78 = 53 25/39

9)6 11/12 + 3 15/16 = 6 44/48 + 3 45/48 = 9 89/48 = 9 41/48