2/3х + 4 1/6 = 5 2/3
2/3х = 5 2/3 - 4 1/6
2/3х = 5 4/6 - 4 1/6
2/3х = 1 3/6
2/3х = 1 1/2
2/3х = 3/2
х = 3/2 : 2/3
х = 3/2 * 3/2
х = 9/4
х = 2 целых 1/4
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Проверка: 2/3 * 9/4 + 4 1/6 = 5 2/3
3/2 + 4 1/6 = 5 2/3
1 3/6 + 4 1/6 = 5 2/3
5 4/6 = 5 2/3