3/4с - 1/2 - 3 = 5/8 - 1/6с
3/4с + 1/6с = 5/8 + 1/2 + 3
9/12с + 2/12с = 5/8 + 4/8 + 3
11/12с = 4 целых 1/8
11/12с = 33/8
с = 33/8 : 11/12
с = 33/8 * 12/11
с = 9/2
с = 4 целых 1/2
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Проверка: 3/4 * 9/2 - 1/2 - 3 = 5/8 - 1/6 * 9/2
27/8 - 4/8 - 3 = 5/8 - 9/12
23/8 - 3 = 5/8 - 3/4
23/8 - 24/8 = 5/8 - 6/8
- 1/8 = - 1/8