Ответ:
Пошаговое объяснение:
(3/4-1/6)*3/7 =(9/12-2/12)*3/7=
7/12*3/7=1/4
(4/15+2/3):2/5=(4/15+10/15):2/5=
14/15*5/2=7/3=2 1/3
(4/9+1/6)*9/11=(8/18+3/18)*9/11=
11/18*9/11=1/2
8/11*(5/6-3/8) =8/11*(20/24-9/24)=
8/11*11/24=1/3
3/5:(4/5-1/2) =3/5:(8/10-5/10)=
3/5*10/3=2
3/8*(7/12+3/4)=3/8*(7/12*9/12)=
3/8*16/12=1/2