7 5/18-3 2/27-11/54 8 7/12-4 5/18-1 1/4
131/18-83/27-11/54 393-166-11/54 216/54=сокращаем 4
103/12-77/18-5/4
309-154-45/36
110/36=сокращаем55/18= 3целых 1/18