4 7/15 - 2 11/20 = 4 28/60 - 2 33/60 = 3 88/60 - 2 33/60 = 3-2 (88-33)/60 = 1 55/60 = 1 11/12
Ответ: 1 11/12
2 - 2
5 - 4
3 - 2
9 - 3
4 - 2
25 - 4
11- 9