Выполните действия 1) (1/12+1/6): (3/8-1/4); 2) (1-4/9): (1/3-1/4); 3) (1/3-5/16): (1/6-1/8); 4) (5/7-2/3): (4/9-5/12);

Пошаговое объяснение:

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

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

(1/3 -5/16) : (1/6-1/8) = (16/48 - 15/48) : (4/24 - 3/24) = 1/48 : 1/24 = 1/48×24/1=24/48=1/2

(5/7 - 2/3) : (4/9 - 5/12) = (15/21 - 14/21) : (16/36 - 15/36) = 1/21 : 1/36 =

= 1/21 * 36/1 = 36/21 = 12/7 = 1 5/7