Ответ:

Пошаговое объяснение:

3. 11/42 - 2. 33/56 =

3. 44/168 - 2. 99/168 =

2. 212/168 - 2. 99/168 =

113/168

2. 13/30 + 1. 3/20 =

2. 26/60 + 1. 9/60 =

3. 35/60 = 3. 7/12

7. 5/18 + 5. 1/12 =

7. 20/72 + 5. 6/72 =

12. 26/72 = 12. 13/36