это вопрос?
1) 8 7/9 - х = 3 5/6
х = 8 7/9 - 3 5/6
х = 8 14/18 - 3 15/18
х = 7 32/18 - 3 15/18
х = 4 17/18
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Проверка: 8 14/18 - 4 17/18 = 7 32/18 - 4 17/18 = 3 15/18 = 3 5/6
2) (х - 5/6) + 11/18 = 19/24
х - 5/6 = 19/24 - 11/18
х - 5/6 = 57/72 - 44/72
х - 5/6 = 13/72
х = 13/72 + 5/6
х = 13/72 + 60/72
х = 73/72
х = 1 целая 1/72
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Проверка: (73/72 - 60/72) + 44/72 = 57/72 = 19/24
