四年级小数简便运算及答案

一、用简便方法计算下面各题：48.7+5.6+11.343.21+98.76+56.79+1.245.48+3.996.3+15.4+0.09+3.7+14.656.8+22.834.65－0.99－0.9734.5－2.9845.7－10.457.3－27.8=48.7+11.3+5.6=60+5.6=65.6=(43.21+56.79)+(98.76+1.24)=100+100=200=5.48+(4－0.01)=5.48+4－0.01=9.47=(6.3+3.7)+(14.6+15.4)+0.09

=40+0.09=40.09=56.8+23－0.2=79.8－0.2=79.6=34.65－1－1+(0.01+0.03)=32.65+0.04=32.69=34.5－3+0.02=31.5+0.02=31.52=45.7－10－0.4=35.7－0.4=35.3=57.3－28+0.2=29.3+0.2=29.567.68－7.3－2.73.65－1.28－0.37－1.7719.826－1.173－5.248－3.405130.8－35.9+5.923.97+0.9+6.823.9+6.78－3.931.61－21.27－1.61=67.68－(7.3+2.7)

=67.68－10=57.68=3.65－(1.28+0.37)－1.77

=3.65－1.65－1.77

=0.23=19.826－(1.173+5.248+3.405

)=19.826－9.826

=10=130.8－(35.9－5.9)

=130.8－30=100.8=23.97+1+7－0.3=31.97－0.3=31.67=23.9－3.9+6.78

=20+6.78=26.78=31.61－1.61－21.27=30－21.27=8.7327.64－(5.79+1.64)23.12－(10.12－3.67)20.65－(17.1－1.35)32.75+(15.25－10.68)30.16－23.28+15.280.25×4.78×40.98×2.5=27.64－1.64－5.79=26－5.79=20.21=23.12－10.12+3.67=13+3.67=16.67=20.65+1.35－17.1=22－17.1=4.9=32.75+15.25－10.68=48－10.68=37.32=30.16－(23.28－15.28)

=30.16－8=22.16=0.25×4×4.78=1×4.78=4.78=(1－0.02)

×2.5=1×2.5－0.02×2.5=2.5－0.05=2.454.52×0.45+5.48×0.4542×3.9

1.4×99+1.40.25×7×3.61.25×13×1.610.2×0.41

2.5×12.5×3242×67+4.2×3308.37×16÷8=0.25×7×(4×0.9）=0.25×4×7×0.9=1×7×0.9=6.3=1.25×13×(8×0.2）=1.25×8×13×0.2=10×13×0.2=26=(10+0.2）×0.41=10×0.41+0.2×0.41=4.1+0.082=4.182=(4.52+5.48）×0.45=10×0.45=4.5=42×(4－0.1）=42×4－42×0.1=168－4.2=163.8=1.4×(99+1）=1.4×100=140=2.5×12.5×(8×4）=(2.5×4)×(12.5×8)=10×100=1000=42×67+42×33=42×(67+33）=42×100=4200=8.37×(16÷8）=8.37×2=16.7428.7÷0.35310÷2.5÷411.2÷9.6×2.4560÷(140÷8)5.6×7÷491÷0.1252.38×4.1+5.8×2.38+0.23828.7×1.6÷28.7=28.7÷(0.7×0.5）=28.7÷0.7÷0.5=41÷0.5=82=310÷(2.5×4）=310÷10=31=11.2÷(9.6÷2.4）=11.2÷4=2.8=560÷140×8=4×8=32=5.6÷4×7=1.4×7=9.8=(91×8)÷(0.125×8）=728÷1=728=2.38×4.1+5.8×2.38+2.38×0.1=2.38×(4.1+5.8+0.1）=2.38×10=23.8=28.7÷28.7×1.6=1×1.6=1.611÷0.25－10÷0.25(80+5.6)÷8=(11－10)÷0.25=1÷0.25=4=80÷8+5.6÷8=10+0.7=10.77.8×(1.001÷0.26)×0.263.5+17.8×99+14.3100×9.5×0.98+9.5×228×11.11+99.99×8=7.8×1.001×(0.26÷0.26)=7.8×1.001=7.8078=(3.5+14.3)+17.8×99=17.8×(1+99）=17.8×100=1780=100×0.98×9.5+9.5×2=9.5×(98+2）=9.5×100=950=28×11.11+11.11×9×8=28×11.11+11.11×(9×8)=11.11×(28+72）=11.11×100=11117.6×18+2.3×2.41.62÷8÷(3.62－2.37)0.38×7.6+0.38÷2.5+0.38×236×2.54+1.8×49.21994+199.4+19.94+1.994=1.62÷8÷1.25=1.62÷(8×1.25）=1.62÷10=0.162=0.38×7.6+0.38×0.4+0.38×2=0.38×(7.6+0.4+2)=0.38×10=3.8=1.8×20×2.54+1.8×49.2=1.8×(20×2.54)+1.8×49.2=1.8×(50.8+49.2)=1.8×100=180=2000+200+20+2－6－0.6－0.06－0.006=2222－6.666=2215.334=0.7×1+(2×2)×0.7+0.7×3+2×0.7=0.7×(1+4+3+2)=0.7×10=70.7+2×1.4+2.1+2×0.7(0.375×101－37.5)÷37.51.1×1.1×11－1.1×1.1－1.11999×19981998－1998×1999199949.5×13.5－0.5×49.5+50.5×13=0.375×(101－1)÷37.5=0.375×100÷37.5=37.5÷37.5=1=1.1×1.1×(11－1)－1.1=1.1×11－1.1=1.1×(11－1)=11=1999×1998×10001－1998×1999×10001=0999×999+1999=999×(1000－1)+1999=999×1000－1×999+1999=999000－999+1999=1000000=49.5×(13.5－0.5)+50.5×13=49.5×13+50.5×13=(49.5+50.5)×13=1300111×36+888×8=111×36+111×8×8=111×(36+64)=1110098×98+97×97－98×97－97×9688×0.1251234×9876－1233×987798+97－96－95+94+93－92－91+……+6+5－4－3+2+1=98×98－98×97+97×97－97×96=98×(98－97)+97×(97－96)=98×1+97×1=197=(80+8)×0.125=80×0.125+8×0.125=10+1=11=1233×9876+1×9876－(1233×9876+1233×1)=9876－1233=8643(8.4+8.4+8.4+8.4)×2.5=8.4×4×2.5=8.4×(4×2.5)=84=(98+97－96－95)+(94+93－92－91)+……+(6+5－4－3)+2+1=4×〔(98－2)÷4〕+2+1=4×24+2+1=990.9+0.99+0.999+0.999912.9÷0.72+43.5÷3.60.268×8.88÷2.68÷4.441.1+1.3+1.5+……+9.7+9.9117.8÷2.3－4.88÷0.2333333×33333=(1+1+1+1)－(0.1+0.01+0.001+0.0001)

=4－0.1111=3.8889=(12.9×5)÷(0.72×5)+43.5÷3.6=64.5÷3.6+43.5÷3.6=(64.5+43.5)÷3.6=30=(0.268÷2.68)×(8.88÷4.44)=0.1×2=0.2=(1.1+9.9)÷2×45=5.5×45=247.5=117.8÷2.3－48.8÷2.3=(117.8－48.8)÷2.3=69÷2.3=300.225×0.335+0.335×0.775+0.775×0.2251992×27.5+1982×72.596÷3.2÷251.6×16+0.4×3614×72+42×76=(1982+10)×27.5+1982×72.5=1982×(27.5+72.5)+10×27.5=198200+275=198475=96÷(0.8×4×25)=96÷80=1.2=0.4×4×16+0.4×36