(7 1/12 - х) - 1 1/3 = 6 13/18 - 2 1/4
Приведём обе части уравнения к общему знаменателю 36
(7 3/36 - х) - 1 12/36 = 6 26/36 - 2 9/36
(7 3/36 - х) - 1 12/36 = 4 17/36
7 3/36 - х = 4 17/36 + 1 12/36
7 3/36 - х = 5 29/36
х = 7 3/36 - 5 29/36
х = 6 39/36 - 5 29/36 = 1 10/36
х = 1 5/18
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Проверка: (7 3/36 - 1 10/36) - 1 12/36 = 6 26/36 - 2 9/36
5 29/36 - 1 12/36 = 4 17/36
4 17/36 = 4 17/36