(7/12)х - 5/18 = 2 4/9
(7/12)х = 2 4/9 + 5/18
(7/12)х = 2 8/18 + 5/18
(7/12)х = 2 13/18
(7/12)х = 49/18
х = 49/18 : 7/12
х = 49/18 · 12/7
х = (7·2)/(3·1)
х = 14/3
х = 4 целых 2/3
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Проверка:
7/12 · 14/3 - 5/18 = 49/18 - 5/18 = 44/18 = 22/9 = 2 4/9.