Ответ:

1) 2

2) 6 2/3

Пошаговое объяснение:

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1) (1/12 + 1/6) : (3/8 - 1/4) = (1/12 + 2/12) : (3/8 - 2/8) = 3/12 : 1/8 = 3/12 * 8/1 = 2/1 = 2

2) (1 - 4/9) : (1/3 - 1/4)= (9/9 - 4/9) : (4/12 - 3/12) = 5/9 : 1/12 = 5/9 * 12/1 = 20/3 = 6 2/3

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