小數(shù)混合運(yùn)算專項(xiàng)訓(xùn)練1、解方程。（1）5x＝450（2）12（6－x）＝42（3）1.2×6+4x＝12（4）8.5x－x＝22.52、用簡(jiǎn)便辦法計(jì)算。（1）0.25×3.2×12.5（2）36×10.1（3）0.25×44（4）22.2×4+17.8×43、用脫式計(jì)算。（1）2.6+1.4×1.5－1.5（2）（37－3.6÷4.8）÷12.5（3）2.6+2.4×（1.4－1.05）（4）15.6÷16×（0.25+1.25）30.8÷[14-(9.85+1.07)][60-(9.5+28.9)]÷0.182.881÷0.43-0.24×3.520×[(2.44-1.8)÷0.4+0.15]28-(3.4+1.25×2.4)2.55×7.1+2.45×7.1777×9+1111×30.8×[15.5-(3.21+5.79)](31.8+3.2×4)÷531.5×4÷(6+3)0.64×25×7.8+2.22÷2.5+2.5÷236.25÷4.25×9.95180－705×624÷2.4－2.5×0.8(4121+2389)÷7671×15-974469×12+149219.4×6.1×2.318.1×0.92+3.930.4×0.7×0.250.78+5.436+14.8×5÷4+1÷49.9x5÷6+5÷610.3÷4x8÷9-1÷314.31x5÷6-5÷616.5÷9x18-14x2÷720.3x2÷9+1÷335.95÷（64-45）36.178-145÷5×6+427.2÷0.8-1.2×56.5×（4.8-1.2×4）28-(3.4+1.25×2.4)2.55×7.1+2.45×7.1777×9+1111×3（31.8+3.2×4）÷531.5×4÷(6+3)0.64×25×7.8+2.22÷2.5+2.5÷2194－64.8÷1.8×0.936.72÷4.25×9.95180－705×624÷2.4－2.5×0.8(4121+2389)÷7671×15-974469×12+1492405×(3213-3189)19.4×6.1×2.35.67×0.2-0.6218.1×0.92+3.930.043×24+0.8750.4×0.7×0.250.78+5.436+14.07×0.86+9.12240×78÷（154-115）1437×27＋27×563〔75-（12+18）〕÷152160÷〔（83-79）×18〕280＋840÷24×5325÷13×(266－250)85×(95－1440÷24)58870÷(105＋20×2)1437×27＋27×56381432÷(13×52＋78)[37.85-（7.85+6.4）]×30（947－599）＋76×6436×(913－276÷23)[192－（54＋38）]×6781432÷(13×52＋78)（947－599）＋76×6460－(9.5＋28.9)÷0.182.881÷0.43－0.24×3.50.8×〔15.5-(3.21+5.79)〕31.83.2×4）÷5194－64.8÷1.8×0.936.72÷4.25×9.93.416÷（0.016×35）0.8×[(10－6.76)÷1.2](6.8-6.8×0.55)÷8.50.12×4.8÷0.12×4.8（58+37）÷（64-9×5）812-700÷（9+31×11）156×[(17.7-7.2)÷3]（3.2×1.5+2.5）÷1.685+14×（14+208÷26）120-36×4÷18+359.72×1.6-18.305÷73.2×（1.5+2.5）÷1.6（58+37）÷（64-9×5）(6.8-6.8×0.55)÷8.50.12×4.8÷0.12×4.8（3.2×1.5+2.5）÷1.6120-36×4÷18+3515-10.75×0.4-5.7347+45×2-4160÷52（58+37）÷（64-9×5）[（7.1-5.6）×0.9-1.15]÷2.5（3.2×1.5+2.5）÷1.65.4÷[2.6×（3.7-2.9）+0.62]12×6÷（12-7.2）-63.2×6+（1.5+2.5）÷1.6（3.2×1.5+2.5）÷1.6120-144÷18+35347+45×2-4160÷52（58+37）÷（64-9×5）95÷（64-45）812-700÷（9+31×11）120-36×4÷18+35(6.8-6.8×0.55)÷8.50.12×4.8÷0.12×4.80.8×〔15.5-(3.21+5.79)〕（31.8+3.2×4）÷531.5×4÷(6+3)0.64×25×7.8+2.22÷2.5+2.5÷2194－64.8÷1.8×0.936.72÷4.25×9.95180－705×624÷2.4－2.5×0.8(4121+2389)÷7671×15-974469×12+1492405×(3213-3189)0.8×[(10－6.76)÷1.2]19.4×6.1×2418.1×0.92+3.9324+0.875×990.4×0.7×0.250.75×102100-56.2331.50＋160÷40（58+370）÷（64-45）32.120-144÷18+3533.347+45×2-4160÷5234（58+37）÷（64-9×5）35.95÷（64-45）36.178-145÷5×6+42420+580-64×21÷2837.812-700÷（9+31×11）（136+64）×（65-345÷23）38.85+14×（14+208÷26）120-36×4÷18+35（58+37）÷（64-9×5）(6.8-6.8×0.55)÷8.50.12×4.8÷0.12×4.8（3.2×1.5+2.5）÷1.63.2×（1.5+2.5）÷1.631.50＋160÷40（58+370）÷（64-45）32.120-144÷18+3533.347+45×2-4160÷5234（58+37）÷（64-9×5）35.95÷（64-45）36.178-145÷5×6+42420+580-64×21÷28812-700÷（9+31×11）（136+64）×（65-345÷23）（284+16）×（512-8208÷18）120-36×4÷18+35（58+37）÷（64-9×5）(6.8-6.8×0.55)÷8.50.12×4.8÷0.12×4.8（3.2×1.5+2.5）÷1.6（23.2×（1.5+2.5）÷1.645.6-1.6÷4=5.38+7.85-5.37=46.7÷0.8-1.2×5=6-1.19×3-0.43=47.6.5×（4.8-1.2×4）=0.68×1.9+0.32×1.9297×9991983