10 целых 6/7 - 3 4 целых 2/13 + 5 целых 7/13 8 целых 7/12 - 4 целых 2/12 4 целых 8/11 = 5 целых 7/11 7 целых 5/9 -2 целых 8/9
10 6/7 - 3 = 7 6/7 4 2/13 + 5 7/13 = 9 9/13 8 7/12 - 4 2/12 = 4 5/12 4 8/11 + 5 7/11 = 10 4/11 7 5/9 - 2 8/9 = 68/9 - 26/9 = 42/9 = 4 6/9