x+2 1/3+3 1/9 - 1 1/12=5 7/12

Х + 2 1/3 + 3 1/9 - 1 1/12 = 5 7/12 
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Х + 2 3/9 + 3 1/9 = 5 7/12 + 1 1/12 
Х + 5 4/9 = 6 8/12 
Х + 5 2/3 = 6 2/3 
Х = 6 2/3 - 5 2/3 
Х = 1