2/7
Пошаговое объяснение:
1) 5 5/18 - 4 7/12 = 5 10/36 - 4 21/36 = 25/36
2) 25/36 * 1 2/25 = 25/36 * 27/25 = 3/4
3) 1 1/4 + 1 3/8 = 1 2/8 + 1 3/8 = 2 5/8
4) 3/4 : 2 5/8 = 3/4 : 21/8 = 3/4 * 8/21 = 2/7
