1) 5 4/5 - 3 = 2 4/5 = (2 * 5 + 4) / 5 = 14/5
2) 7 1/9 - 3 = 4 1/9 = (4 * 9 + 1) / 9 = 37/9
3) 9 9/19 - 3 = 6 9/19 = (6 * 19 + 9) / 19 = 123/19
Ответ: 14/5, 37/9, 123/19