一、怎样简便就怎样算。
4/9÷【4/5-(1/5+1/3)】
1/3+3-(1/4+1/2)
3×(2/15+1/12)-2/5
3/4×5/7×4/3-1/2
15/16+(7/16-1/4)÷1/2
23-8/9×3/8÷1/27
(1/3-1/4)÷1/2+5/6
1/2×3+1/2÷1/5
2/3+(4/7+1/2)×7/25
8×5/6+2/5÷4
【1/2-(3/4-3/5)】÷7/10
1/5+2/7÷3/7
1/2×2/5+9/10÷9/20
1/3÷(2/3-2/5)×3/5
(11/12-3/4)÷(2-1/2)
5/9×3/10+2/7÷2/5
二、解方程。
1/4X+2X=1/2
5X-5/6=5/12
2/3X-20%X=1
X+7/9X=4/3