Целую часть отделяю пробелом
55. 1) 9 - 1 5/6 = 8 6/6 - 1 5/6 = 7 1/6
2) 8 - 2 1/3 = 7 3/3 - 2 1/3 = 5 2/3
3) 11 - 3 3/8 = 10 8/8 - 3 3/8 = 7 5/8
4) 12 - 4 3/7 = 11 7/7 - 4 3/7 = 7 4/7
56. 1) 2 9/10 - 4/5 = 2 9/10 - 8/10 = 2 1/10
2) 6 7/15 - 1/3 = 6 7/15 - 5/15 = 6 2/15
3) 8 11/12 - 1/2 = 8 11/12 - 6/12 = 8 5/12
4) 5 3/4 - 2/5 = 5 15/20 - 8/20 = 5 7/20