(1)5×2+4×2=18(2)1×1/2+3×2/3=14/3(3)2.5*32*0.125=(2.5*4)*(8*0.125)=10*1=10(4)3.5-7+6.5=3.5+6.5-7=328×12.5-12.5×20=(28-20)*12.5=8*12.5=100(4+0.4×0.25)8×7×1.25=(4+1)*7*10=5*7*10=3501.65×99+1.65 =1.65*(99+1)=1.65*100=16548×1.25+50×1.25×0.2×8 =1607.8×9.9+0.78 =7.8*(9.9+0.1)=7.8*10=784.8×46+4.8×54 =(46+54)*4.8=100*4.8=480(23/4-3/4)×(3×6+2) =10012× 5/6 – 2/9 ×3 8× 5/4 + 1/4 =10又1/46÷ 3/8 – 3/8 ÷6 =15又3/4