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 |