1)
(1/12+1/6):(3/8- 1/4)
2)
(1-4/9):(1/3-1/4​

1) 2

2) 6 2/3

Пошаговое объяснение:

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