Пошаговое объяснение:

7 - 6 4/5 = 6 5/5 - 6 4/5 = 1/5

8 - 3 2/13 = 7 13/13 - 3 2/13 = 4 11/13

4 4/7 - 1/14 = 4 8/14 - 1/14 = 4 7/14 = 4 1/2