(1) 3X-(1/2+1/4)=7/12 3X=7/12+3/4 3X=4/3 X=4/9 (2) 6.6-5X=3/4-4X 6.6-0.75=-4X+5X X=5.85 (3) 1.1X+2.2=5.5-3.3X 1.1X+3.3X=5.5-2.2 4.4X=3.3 X=3/4=4/3 还有(0.5+x)+x=9.8÷2 2(X+X+0.5)=9.8 25000+x=6x 3200=4...