脱式计算练习试题
21道脱式计算
21道脱式计算脱式计算是指在计算过程中，通过快速的心算或者简单的计算步骤，来快速得到答案的方法。
在日常生活中，我们经常会遇到需要进行脱式计算的情况，比如结账、测量、调整时间等。
下面将介绍21道脱式计算的例题，帮助大家提高计算速度和准确度。
1. 36 + 27 =2. 58 - 19 =3. 84 × 3 =4. 125 ÷ 5 =5. 72 + 43 - 29 =6. 56 × 4 ÷ 2 =7. 98 ÷ 7 + 15 =8. 124 - 37 + 49 =9. 83 × 6 - 25 =10. 195 ÷ 15 + 7 =11. 62 + 48 - 29 + 15 =12. 72 ÷ 8 × 6 - 5 =13. 58 - 24 ÷ 3 + 10 =14. 126 + 84 - 37 =15. 189 ÷ 7 × 3 =16. 46 + 27 ÷ 9 =17. 95 - 63 ÷ 7 =18. 72 × 4 ÷ 6 =19. 136 ÷ 17 + 25 =20. 78 + 64 ÷ 8 =21. 94 ÷ 2 + 7 × 3 =以上是21道脱式计算的例题，通过练习这些计算题目，可以提高我们的计算能力和速度。
在进行脱式计算时，首先要掌握基本的加减乘除法运算规则，然后通过适当的分步计算和简化计算的方法，来快速得到正确的答案。
通过不断练习，我们可以在日常生活中更快更准确地完成各种计算任务，提高工作和生活效率。
希望以上内容能够帮助大家更好地掌握脱式计算的方法和技巧，提升计算能力。
(完整)小数除法脱式运算+简算260道含答案,推荐文档
小数除法脱式运算+简算260道一．计算题（共50小题）1．用你喜欢的方法计算．32×12.5×0.25 6.1×4.2+5.8×6.1 1.7÷2.5÷0.416.1﹣4.2﹣5.8．3．脱式计算4.8÷（1.2÷0.5）12.8﹣12.8÷571.4÷（7×6）4．用你喜欢的方法计算0.65×101﹣0.65 12.6﹣3.25+6.756.35÷0.2÷0.5 5.7×1.2÷19 1.25×3.63×0.8．5．我能用喜欢的方法计算下面各题．0.11×1.8+8.2×0.11 3.5﹣3.5×0.980.75×18÷0.150.25×4.78×8．6．能简算的要简算．17.3÷0.125÷8 14.72×0.7+5.28×0.73.5÷0.56 8.5×9.9+0.82．7．递等式计算，有简便运算的用简便方法38.75﹣（24.5+8.75）0.4×2.32×0.250.75×101 4.2﹣3.2×0.97.56×99+7.5670.3﹣17.48÷7.6 3.64÷5.2×23.321.8÷0.8﹣1.2×5 45÷（5.25÷0.25）16.5×101﹣16.50.96÷0.3×14 1.25×4×2.5×836.45÷（0.82+3.4×0.2）9.07﹣2.64÷0.4 1.5×10112.6×7.5+8.3 13.6×0.85﹣3.6×0.85104×8.586.4÷6.4﹣0.40.25×6.2×0.4 23×6.5+17×6.536÷0.4×0.25（24.6﹣18.1）×3.47.6×9.9+7.6×0.113.6×0.8×12.523.9×8.5﹣3.9×8.5（2.55+9.6÷16）÷0.429.2÷0.25÷48．脱式计算（能简算的要简算）0.75×4×0.25×49.6+9.9×9915.58÷8.2﹣0.724.536÷0.8÷14 2.8×3.6+1.4×2.8 6.3×10.1．9．脱式计算（能简算的要用简算）4.2×7.8+2.2×4.2 9.5×101（8×3.82）×1.25 0.125×720.6×3.9×0.8 42×0.39+4.2×6.110．脱式计算，能简算的要简算0.25×1.25×1618.9﹣18.9÷1.48.37×1.2﹣8.37×0.243×11.8+5.7×118．11．用简便方法计算．6.2+5.18+2.8 15.35﹣（5.35+7.2）3.63﹣1.25+17.37﹣8.75 51.72﹣8.66﹣1.34．12．脱式计算，能简算的要简算．0.7×101﹣0.7 0.125×4.95×8 12.9﹣1.68﹣2.32 567÷20÷5．13．用递等式计算，能简算的要简算．20.16÷7.2+9.8 6.2×2.7+6.5×7.3 32.8+9.6+7.2．14．脱式计算：能简算的要简算15.89﹣（5.89+6.98）0.25×13.7×0.432.7×28+7.3×2815×9.4﹣42 4.9+12.87﹣5.380.05×0.7×20×1.7．15．计算下面各题，能简算的要简算．5.04×28（15.4﹣7.8）×3.5 3.2×4.6+3.2×5.40.25×17.4×4 20﹣6.72﹣3.28 8.33+7.45+1.67+2.55 16．脱式计算．0.2×0.6×0.5×4 （7.5﹣2.3×0.4）÷0.011.2×0.25+2.8×0.25 178.8÷（26.4﹣5.6）17．能简算的要简算3.6﹣1.28+3.09 3.82+2.9+0.18+9.1 9.43﹣（6.28﹣1.57）21.32﹣（6.32+8.3）13.75﹣（3.75+6.48）15﹣7.35﹣2.6518．混合运算，能简便就简便19.81﹣2.68﹣8.32 5.6+6.6﹣5.6+6.60.81×27+0.19×27101×0.19﹣0.19．19．用简便方法计算9.08﹣1.76﹣4.24 18.38﹣（5.38+1.8）﹣8.217.45﹣（8.76﹣6.55）12.87+3.98﹣3.87．20．脱式计算，能简便的用简便方法计算．10.8÷（3.94+6.86）×0.8 0.65×201 12.5×3.9×0.839.8×0.25×4 37.6×8+37.6×2 0.78×99+0.78．21．脱式计算：21.8﹣7.22﹣2.78 9﹣0.24÷1.6×1.19.12+9.12×9﹣6.02 45.2×66.7+66.7×53.8+66.70.25×0.8×0.125×0.4 12.75÷[14.6﹣（1.3+8.2）]0.125×36×（4÷0.5）÷36[（6.1﹣4.6）×0.8﹣1]×0.3615.6﹣（4.1+0.2+6.86÷0.7）[5﹣（1﹣1.2×0.8）]÷41÷0.25+0.4×0.6 13.6×3﹣40.6÷2 25.8+10.5÷（5﹣3.5） 1.42﹣0.36÷6×0.6 49.5×0.2﹣2.07÷23 6.7+3.3÷4.4+5.622．计算下面各题（能简算的要简算）50×（0.8+0.4）7.34×2.1+7.34×6.8+7.34×1.120.5÷1.25÷0.8 9.88×9+9.88．23．计算下列各题（能用简便算法的要用简便算法）．12.6÷（1.02+3.18） 5.7×6.9+4.3×6.9（0.81+2.7）÷0.9[（8.4﹣7.9）÷0.25]×1.2．25．能简算的用简便方法计算．（写出主要简便过程，无过程不得分）1.6×3.9×1.25 4.87×2.34+48.7×0.2660.49×9.9 0.05×0.7×20×1.72.5×3.2×12.5 3.95×7.6+3.95×3.4﹣3.95．26．计算下面各题，能简算的要简算7.8×6.9+2.2×6.9 2.36×2.5×4102×0.454.19×99+4.1921.36÷0.8﹣12.9 3.2÷0.8×0.2627．计算（能简算的要简算）．6.33×101﹣6.33 1.6×55.4﹣55.4×0.617.68÷5.2+2.7×1.5（1.1﹣0.78）×（2.7﹣1.95）35.6﹣5×1.7315÷0.2÷2.528．脱式计算（能简算的要简算）2.5×1.37×0.4 4.8×0.25×250.89×4.8+0.89×5.2 101×0.78×208.8×1.25×15 4.3×0.8×529．计算下面各题，能简算的要简算．44.28÷0.9÷4.10.25×0.39×47.6+7.6×99 9.07﹣22.78÷3.4 4.8×99+4.8 6.3×10.1 30．下面各题，能简算的就要简算．5.8+3.8×0.25 1.7×（4.65﹣3.87） 1.25×4.3×0.84.5×1020.54×101﹣0.54 3.4×2.5+6.6×2.5．31．计算下列各题．0.45×12×0.2 6.2×2.1﹣2.1 0.9×0.8×1002.8﹣2.8×0.15 2.8×1.43+0.57 72×0.81+10.310﹣6.06+8.5 6×0.25×1.8 7.06×2.4﹣5.832．用简便方法计算．0.25×9.87×4 36.2×1.8+13.8×1.8 0.125×2.3×80.73×102 （6.8+2.6）×5 0.23×98．33．能用简便方法的用简便方法计算12.5×32×2.5 6.8×9.9 7.2÷[1.8×（3.4﹣2.9）]．34．用你喜欢的方法计算．3.4×9+3.4 6.4÷0.8﹣1.5×4 3.78÷0.25÷4 17÷[（1.2+0.5）×5]．35．用你喜欢的方法计算2.5×1.25×8×0.4 12.8×1.7+87.2×1.7 100﹣4.35﹣5.65．36．用递等式计算（能简算的要简算）．4+7.6×15 26.08÷0.25÷419.7+（80.5÷35×0.2）37．计算，能简算的要简算．1.25×2.25×0.8 9.7×99+9.7 4.8×7.8+78×0.523.65×10.1．38．计算下面各题．（能简算的用简便算法）①12.36﹣6.49﹣3.51②8.5×3.8+8.5×6.2③17.3×0.25×8④15.32﹣1.8×5﹣3.46⑤199×2.6⑥3.6÷[（1.3+0.6）×5]39．计算8.5+6.85﹣6.35 3.9+0.1﹣3.9+0.1 12.6﹣（3.75+5.08）40．计算，能简算的要简算6.09﹣9.13÷8.3 3.84×9.6+0.96×61.6 4.86×995.68×4+4.32÷0.256.4×4.5+3.6×4.5．41．脱式计算．10.5+61×18 （3.14+12.6）÷8 4.5÷（15÷3）75+448÷4×19．42．计算：（18.5×3.8+3.8×2.5）÷0.19 [32﹣（7.25+0.75×8）]÷50．43．脱式计算，能简算的就简算：25.32﹣（3.4﹣1.2）12﹣0.62﹣4.38．44．用简便方法计算下面各题．5.12+2.54+4.88 12.5×17.8×0.8 0.24×0.48×49.9×2.5 9.4×5.8+10.6×5.8 0.66×101 4.8×0.25 2.33×0.5×4 1.3×2.5+0.7×2.5 1.26×0.6+1.26×0.4 102×0.55 0.034×0.5×0.245．计算．（怎样简便就怎么计算）13.38+0.98=7.02﹣2.98 6.57﹣（0.68﹣0.39+0.32）13.8÷（1.38×0.2）30.7﹣0.12×2﹣0.76 7.8×1.0118.4﹣6.5+1.6+3.5 7.8÷0.6+7.8÷0.412.13+7.5﹣1.13+2.85 0.125×8.89.4×3.2+6×0.32 9.6×3.6+7.2×0.2．46．计算下面各题，能简算得要简算．96÷（100×0.48） 3.6÷（1.2+0.5）×6（967﹣31）÷（17+48）72×10.1+27×10.1．47．用自己喜欢的方法计算．3.4×7.8÷3.9 54÷（6.86+3.94）48．用简便方法计算0.486+0.01+3.99 17.5×2.3﹣7.5×2.3 1.25×11×4×0.84.8×39+61×4.8 45.55﹣（6.82+15.55） 3.2×99+3.22.5×56+4.5×56 （31.6﹣11.7）÷2.5÷43.6×0.9+3.6×0.149．计算下列各题．（能简算的要简算）7.5﹣2.4÷0.8×2.5 12.5×17+83×12.5399×2.5 25÷（2.5÷0.4）3.25×67+5.75×67+67 230÷2.5×7.5 6.3+0.84+3.7+8.16 100﹣（2.72+10.8）÷0.250．脱式计算0.25×3.25×4 6.72+3.2÷2.521.36÷0.4﹣23.40.8×4.5+1.2×4.5．小数除法脱式运算+简算260道参考答案与试题解析 一．计算题（共50小题）1．【解答】解：（1）32×12.5×0.25=4×8×12.5×0.25=（4×0.25）×（8×12.5）=1×100=100（2）6.1×4.2+5.8×6.1=6.1×（4.2+5.8）=6.1×10=61（3）1.7÷2.5÷0.4=1.7÷（2.5×0.4）=1.7÷1=1.7（4）16.1﹣4.2﹣5.8=16.1﹣（4.2+5.8）=16.1﹣10=6.1 2．【解答】解：（1）（0.6×0.8+0.12）÷1.2=0.6÷1.2=0.5答：商是0.5．（2）（14.81+5.19）×（14.81﹣5.19）=20×9.62=192.4答：积是192.4．（3）[（2.7+4.5）÷12]×0.3=[7.2÷12]×0.3=0.6×0.3=0.18答：积是0.18． 3．【解答】解：①4.8÷（1.2÷0.5）=4.8÷2.4=2②12.8﹣12.8÷5=12.8﹣2.56=10.24③71.4÷（7×6）=71.4÷7÷6=10.2÷6=1.7 4．【解答】解：①0.65×101﹣0.65=0.65×（101﹣1）=0.65×100=65②12.6﹣3.25+6.75=12.6+（6.75﹣3.25）=12.6+3.5=16.1③6.35÷0.2÷0.5=6.35÷（0.2×0.5）=6.35÷0.1=63.5④5.7×1.2÷19=5.7÷19×1.2=0.3×1.2=0.36⑤1.25×3.63×0.8=（1.25×0.8）×3.63=1×3.63=3.63 5．【解答】解：①0.11×1.8+8.2×0.11=0.11×（1.8+8.2）=0.11×10=1.1②3.5﹣3.5×0.98=3.5×（1﹣0.98）=3.5×0.02=0.07③0.75×18÷0.15=0.75÷0.15×18=5×18=90④0.25×4.78×8=0. 25×8×4.78=2×4.78=9.56 6．【解答】解：①17.3÷0.125÷8=17.3÷（0.125×8）=17.3÷1=17.3②14.72×0.7+5.28×0.7=（14.72+5.28）×0.7=20×0.7=14③3.5÷0.56=（3.5÷0.7）÷（0.56÷0.7）=5÷8=0.625④8.5×9.9+0.82=8.5×（10﹣0.1）+0.82=8.5×10﹣8.5×0.1+0.82=85﹣0.85+0.82=85﹣（0.85﹣0.82）=85﹣0.03=84.97 7．【解答】解：（1）38.75﹣（24.5+8.75）=38.75﹣24.5﹣8.75=38.75﹣8.75﹣24.5=30﹣24.5=5.5；（2）0.4×2.32×0.25=0.4×0.25×2.32=0.1×2.32=0.232；（3）0.75×101=0.75×（100+1）=0.75×100+0.75×1=75+0.75=75.75；（4）4.2﹣3.2×0.9=4.2﹣2.88=1.32；（5）7.56×99+7.56=7.56×（99+1）=7.56×100=756；（6）70.3﹣17.48÷7.6=70.3﹣2.3=68；（7）3.64÷5.2×23.3=0.7×23.3=16.31；（8）21.8÷0.8﹣1.2×5=27.25﹣6=21.25；（9）45÷（5.25÷0.25）=45÷21=；（10）16.5×101﹣16.5=16.5×（101﹣1）=16.5×100=1650；（11）0.96÷0.3×14=3.2×14=44.8；（12）1.25×4×2.5×8=（1.25×8）×（4×2.5）=10×10=100；（13）36.45÷（0.82+3.4×0.2）=36.45÷（0.82+0.68）=36.45÷1.5=24.3；（14）9.07﹣2.64÷0.4=9.07﹣6.6=2.47；（15）1.5×101=1.5×（100+1）=1.5×100+1.5×1=150+1.5=151.5；（16）12.6×7.5+8.3=94.5+8.3=102.8；（17）13.6×0.85﹣3.6×0.85=（13.6﹣3.6）×0.85=10×0.85=8.5；（18）104×8.5=（100+4）×8.5=100×8.5+4×8.5=850+34=884；（19）86.4÷6.4﹣0.4=13.5﹣0.4=13.1；（20）0.25×6.2×0.4=0.25×0.4×6.2=0.1×6.2=0.62；（21）23×6.5+17×6.5=（23+17）×6.5=40×6.5=260；（22）36÷0.4×0.25=90×0.25=22.5；（23）（24.6﹣18.1）×3.4=6.5×3.4=22.1；（24）7.6×9.9+7.6×0.1=7.6×（9.9+0.1）=7.6×10=76；（25）13.6×0.8×12.5=13.6×（0.8×12.5）=13.6×10=136；（26）23.9×8.5﹣3.9×8.5=（23.9﹣3.9）×8.5=20×8.5=170；（27）（2.55+9.6÷16）÷0.42=（2.55+0.6）÷0.42=3.15÷0.42=7.5；（28）9.2÷0.25÷4=9.2÷（0.25×4）=9.2÷1=9.2． 8．【解答】解：（1）0.75×4×0.25×4=（0.75×4）×（0.25×4）=3×1=3（2）9.6+9.9×99=9.6+9.9×（100﹣1）=9.6+9.9×100﹣9.9=9.6+990﹣9.9=989.7（3）15.58÷8.2﹣0.72=1.9﹣0.72=1.18（4）4.536÷0.8÷14=5.67÷14=0.405（5）2.8×3.6+1.4×2.8=2.8×（3.6+1.4）=2.8×5=14（6）6.3×10.1=6.3×（10+0.1）=6.3×10+6.3×0.1=63+0.63=63.63 9．【解答】解：（1）4.2×7.8+2.2×4.2=4.2×（7.8+2.2 ）=4.2×10=42（2）9.5×101=9.5×（100+1）=9.5×100+9.5=950+9.5=959.5（3）（8×3.82）×1.25 =（8×1.25）×3.82=10×3.82=38.2（4）0.125×72=0.125×8×9=1×9=9（5）0.6×3.9×0.8 =2.34×0.8=1.872（6）42×0.39+4.2×6.1=42×0.39+42×0.61=42×（0.39+0.61）=42×1=42 10．【解答】解：（1）0.25×1.25×16=0.25×1.25×（2×8）=（0.25×2）×（1.25×8）=0.5×10=5（2）18.9﹣18.9÷1.4=18.9﹣13.5=5.4（3）8.37×1.2﹣8.37×0.2=8.37×（1.2﹣0.2）=8.37×1=8.37（4）43×11.8+5.7×118=43×11.8+57×11.8=（43+57）×11.8=100×11.8=1180 11．【解答】解：（1）6.2+5.18+2.8 =6.2+2.8+5.18 =9+5.18=14.18 （2）15.35﹣（5.35+7.2）=15.35﹣5.35﹣7.2=10﹣7.2=2.8（3）3.63﹣1.25+17.37﹣8.75=（3.63+17.37）﹣（1.25+8.75）=21﹣10=11（4）51.72﹣8.66﹣1.34=51.72﹣（8.66+1.34）=51.72﹣10=41.72 12．【解答】解：（1）0.7×101﹣0.7 =0.7×（101﹣1）=0.7×100=70（2）0.125×4.7×8=0.125×8×4.7=1×4.7=4.7（3）12.9﹣1.68﹣2.32=12.9﹣（1.68+2.32）=12.9﹣4=8.9（4）567÷20÷5=567÷（20×5）=567÷100=5.67 13．【解答】解：①20.16÷7.2+9.8 =2.8+9.8=12.6；②6.2×2.7+6.5×7.3 =16.74+47.45=64.19；③32.8+9.6+7.2=9.6+（32.8+7.2）=9.6+40=49.6． 14．【解答】解：（1）15.89﹣（5.89+6.98）=15.89﹣5.89﹣6.98=10﹣6.98=3.02；（2）0.25×13.7×0.4=0.25×0.4×13.7=0.1×13.7=1.37；（3）32.7×28+7.3×28=（32.7+7.3）×28=40×28=1120；（4）15×9.4﹣42=141﹣42=99；（5）4.9+12.87﹣5.38=17.77﹣5.38=12.39；（6）0.05×0.7×20×1.7=0.05×20×0.7×1.7=1×0.7×1.7=0.7×1.7=1.19． 15．【解答】解：（1）5.04×28=（5+0.04）×28=5×28+0.04×28=140+1.12=141.12；（2）（15.4﹣7.8）×3.5 =7.6×3.5 =26.6；（3）3.2×4.6+3.2×5.4=3.2×（4.6+5.4）=3.2×10=32；（4）0.25×17.4×4=0.25×4×17.4=1×17.4=17.4；（5）20﹣6.72﹣3.28=20﹣（6.72+3.28）=20﹣10=10；（6）8.33+7.45+1.67+2.55=8.33+1.67+7.45+2.55=（8.33+1.67）+（7.45+2.55）=10+10=20． 16．【解答】解：（1）0.2×0.6×0.5×4 =（0.2×0.5）×（0.6×4）=0.1×2.4=0.24；（2）（7.5﹣2.3×0.4）÷0.01=（7.5﹣0.92）÷0.01=6.58÷0.01=658；（3）1.2×0.25+2.8×0.25=（1.2+2.8）×0.25=4×0.25=1；（4）178.8÷（26.4﹣5.6）=178.8÷20.8=． 17．【解答】解：（1）3.6﹣1.28+3.09=2.32+3.09=5.41（2）3.82+2.9+0.18+9.1 =（3.82+0.18）+（9.1+2.9）=4+12=16（3）9.43﹣（6.28﹣1.57）=9.43+1.57﹣6.28=11﹣6.28=4.72（4）21.32﹣（6.32+8.3）=21.32﹣6.32﹣8.3=15﹣8.3=6.7（5）13.75﹣（3.75+6.48）=13.75﹣3.75﹣6.48=10﹣6.48=3.52（6）15﹣7.35﹣2.65=15﹣（7.35+2.65）=15﹣10=5 18．【解答】解：①19.81﹣2.68﹣8.32=19.81﹣（2.68+8.32）=19.81﹣11=8.81②5.6+6.6﹣5.6+6.6=（5.6﹣5.6）+（6.6+6.6）=0+13.2=13.2③0.81×27+0.19×27=27×（0.81+0.19）=27×1=27④101×0.19﹣0.19=（101﹣1）×0.19=100×0.19=19 19．【解答】解：（1）9.08﹣1.76﹣4.24 =9.08﹣（1.76+4.24）=9.08﹣6=3.08；（2）18.38﹣（5.38+1.8）﹣8.2=18.38﹣7.18﹣8.2=11.2﹣8.2=3；（3）17.45﹣（8.76﹣6.55）=17.45﹣8.76+6.55=17.45+6.55﹣8.76=24﹣8.76=15.24；（4）12.87+3.98﹣3.87=12.87﹣3.87+3.98=9+3.98=12.98． 20．【解答】解：①10.8÷（3.94+6.86）×0.8 =10.8÷10.8×0.8=1×0.8=0.8②0.65×201 =0.65×（200+1）=0.65×200+0.65×1=130+0.65=130.65③12.5×3.9×0.8=12.5×0.8×3.9=10×3.9=39④39.8×0.25×4 =39.8×（0.25×4）=39.8×1=39.8⑤37.6×8+37.6×2 =37.6×（8+2）=37.6×10=376 ⑥0.78×99+0.78=0.78×（99+1）=0.78×100=78 21．【解答】解：（1）21.8﹣7.22﹣2.78=21.8﹣（7.22+2.78）=21.8﹣10=11.8（2）9﹣0.24÷1.6×1.1=9﹣0.15×1.1=9﹣0.165=8.835（3）9.12+9.12×9﹣6.02=9.12×（1+9）﹣6.02=9.12×10﹣6.02=91.2﹣6.02=85.18（4）45.2×66.7+66.7×53.8+66.7=（45.2+53.8+1）×66.7=100×66.7=6670（5）0.25×0.8×0.125×0.4=（0.25×0.4）×（0.125×0.8）=0.1×0.1=0.01（6）12.75÷[14.6﹣（1.3+8.2）]=12.75÷[14.6﹣9.5]=12.75÷5.1=2.5（7）0.125×36×（4÷0.5）÷36=0.125×（4÷0.5）×（36÷36）=0.125×8×1=1（8）[（6.1﹣4.6）×0.8﹣1]×0.36=[1.5×0.8﹣1]×0.36=[1.2﹣1]×0.36=0.2×0.36=0.072（9）15.6﹣（4.1+0.2+6.86÷0.7）=15.6﹣（4.1+0.2+9.8）=15.5﹣（4.1+10）=15.5﹣14.1=1.4（10）[5﹣（1﹣1.2×0.8）]÷4=[5﹣（1﹣0.96）]÷4=[5﹣0.04]÷4=4.96÷4=1.24（11）1÷0.25+0.4×0.6=4+0.24=4.24（12）13.6×3﹣40.6÷2=40.8﹣20.3=20.5（13）25.8+10.5÷（5﹣3.5）=25.8+10.5÷1.5=25.8+7=32.8（14）1.42﹣0.36÷6×0.6=1.42﹣0.36=1.07（15）49.5×0.2﹣2.07÷23=9.9﹣0.09=9.81（16）6.7+3.3÷4.4+5.6=6.7+0.75+5.6=7.45+5.6=13.05 22．【解答】解：①50×（0.8+0.4）=50×0.8+50×0.4=40+20=60②7.34×2.1+7.34×6.8+7.34×1.1=7.34×（2.1+6.8+1.1）=7.34×10=73.4③20.5÷1.25÷0.8=20.5÷（1.25×0.8）=20.5÷1=20.5④9.88×9+9.88=9.88×（9+1）=9.88×10=98.8 23．【解答】解：（1）12.6÷（1.02+3.18）=12.6÷4.2=3；（2）5.7×6.9+4.3×6.9=（5.7+4.3）×6.9=10×6.9=69；（3）（0.81+2.7）÷0.9=3.51÷0.9=3.9；（4）[（8.4﹣7.9）÷0.25]×1.2=[0.5÷0.25]×1.2=2×1.2=2.4． 24．【解答】解：（1）25×1.25×32 =25×1.25×8×4=（25×4）×（1.25×8）=100×10=1000（2）（+）×35=×35+×35=10+7=17（3）78×=（79﹣1）×=79×﹣=3﹣=2（4）÷+=÷= 25．【解答】解：（1）1.6×3.9×1.25=0.8×2×3.9×1.25=（0.8×1.25）×（2×3.9）=1×7.8=7.8（2）4.87×2.34+48.7×0.266=4.87×2.34+4.87×2.66=4.87×（2.34+2.66）=4.87×5=24.35（3）0.49×9.9 =0.49×（10﹣0.1）=0.49×10﹣0.49×0.1=4.9﹣0.049=4.851（4）0.05×0.7×20×1.7=（0.05×20）×（0.7×1.7）=1×1.19=1.19（5）2.5×3.2×12.5 =2.5×0.4×8×12.5 =（2.5×0.4）×（8×12.5）=1×100=100（6）3.95×7.6+3.95×3.4﹣3.95=3.95×（7.6+3.4﹣1）=3.95×10=39.5 26．【解答】解：（1）7.8×6.9+2.2×6.9=（7.8+2.2）×6.9=10×6.9=69（2）2.36×2.5×4=2.36×（2.5×4）=2.36×10=23.6（3）102×0.45=（100+2）×0.45=100×0.45+2×0.45=45+0.9=45.9（4）4.19×99+4.19=4.19×（99+1）=4.19×100=419（5）21.36÷0.8﹣12.9=26.7﹣12.9=13.8（6）3.2÷0.8×0.26=4×0.26=1.04 27．【解答】解：（1）6.33×101﹣6.33=6.33×（101﹣1）=6.33×100=633；（2）1.6×55.4﹣55.4×0.6=（1.6﹣0.6）×55.4=1×55.4=55.4；（3）17.68÷5.2+2.7×1.5=3.4+4.05=7.45；（4）（1.1﹣0.78）×（2.7﹣1.95）=0.32×0.75=0.24；（5）35.6﹣5×1.73=35.6﹣8.65=26.95；（6）15÷0.2÷2.5=15÷（0.2×2.5）=15÷0.5=30． 28．【解答】解：（1）2.5×1.37×0.4=2.5×0.4×1.37=1×1.37=1.37；（2）4.8×0.25×25=（4×4×0.3）×0.25×25=（4×0.25）×（4×25）×0.3=1×100×0.3=30；（3）0.89×4.8+0.89×5.2=0.89×（4.8+5.2）=0.89×10=8.9；（4）101×0.78×20=101×（0.78×20）=101×15.6=（100+1）×15.6=100×15.6+1×15.6=1560+15.6=1575.6；（5）8.8×1.25×15=（8×1.1）×1.25×15=（8×1.25）×（1.1×15）=10×16.5=165；（6）4.3×0.8×5=4.3×（0.8×5）=4.3×4=17.2． 29．【解答】解：（1）44.28÷0.9÷4.1=49.2÷4.1=12；（2）0.25×0.39×4=（0.25×4）×0.39=1×0.39=0.39；（3）7.6+7.6×99=7.6×（1+99）=7.6×100=760；（4）9.07﹣22.78÷3.4=9.07﹣6.7=2.37；（5）4.8×99+4.8=4.8×（99+1）=4.8×100=480；（6）6.3×10.1=6.3×（10+0.1）=6.3×10+6.3×0.1=63+0.63=63.63． 30．【解答】解：（1）5.8+3.8×0.25=5.8+0.95=6.75（2）1.7×（4.65﹣3.87）=1.7×0.78=1.326（3）1.25×4.3×0.8=1.25×0.8×4.3=1×4.3=4.3（4）4.5×102=4.5×（100+2）=4.5×100+4.5×2=450+9=459（5）0.54×101﹣0.54=0.54×（101﹣1）=0.54×100=54（6）3.4×2.5+6.6×2.5=（3.4+6.6）×2.5=10×2.5=25 31．【解答】解：①0.45×12×0.2=0.45×0.2×12=0.09×12=1.08 ②6.2×2.1﹣2.1=2.1×（6.2﹣1）=2.1×5.2=10.92③0.9×0.8×100=0.72×100=72④2.8﹣2.8×0.15 =2.8×（1﹣0.15）=2.8×0.85=2.38 ⑤2.8×1.43+0.57 =4.004+0.57=4.574⑥72×0.81+10.3=58.32+10.3=68.62⑦10﹣6.06+8.5=3.94+8.5=12. 44 ⑧6×0.25×1.8 =1.5×1.8=2.7⑨7.06×2.4﹣5.8 =16.944﹣5.8=11.144 32．【解答】解：（1）0.25×9.87×4 =0.25×4×9.87=1×9.87=9.87；（2）36.2×1.8+13.8×1.8 =（36.2+13.8）×1.8=50×1.8=90；（3）0.125×2.3×8=0.125×8×2.3=1×2.3=2.3；（4）0.73×102 =0.73×（100+2）=0.73×100+0.73×2=73+1.46=74.46；（5）（6.8+2.6）×5 =6.8×5+2.6×5=34+13=47；（6）0.23×98=0.23×（100﹣2）=0.23×100﹣0.23×2=23﹣0.46=22.54． 33．【解答】解：（1）12.5×32×2.5=12.5×4×8×2.5=（12.5×8）×（2.5×4）=100×10=1000；（2）6.8×9.9 =6.8×（10﹣0.1）=6.8×10﹣6.8×0.1=68﹣0.68=67.32；（3）7.2÷[1.8×（3.4﹣2.9）]=7.2÷[1.8×0.5]=7.2÷0.9=8． 34．【解答】解：（1）3.4×9+3.4=30.6+3.4=34；（2）6.4÷0.8﹣1.5×4=8﹣6=2；（3）3.78÷0.25÷4=3.78÷（0.25×4）=3.78÷1=3.78；（4）17÷[（1.2+0.5）×5]=17÷[1.7×5]=17÷8.5=2． 35．【解答】解：（1）2.5×1.25×8×0.4=（2.5×0.4）×（1.25×8）=1×10=10；（2）12.8×1.7+87.2×1.7=（12.8+87.2）×1.7=100×1.7=170；（3）100﹣4.35﹣5.65=100﹣（4.35+5.65）=100﹣10=90． 36．【解答】解：（1）4+7.6×15 =4+114=118；（2）26.08÷0.25÷4=26.08÷（0.25×4）=26.08÷1=26.08；（3）19.7+（80.5÷35×0.2）=19.7+（2.3×0.2）=19.7+0.46=20.16． 37．【解答】解：（1）1.25×2.25×0.8=1.25×0.8×2.25=1×2.25=2.25；（2）9.7×99+9.7=9.7×（99+1）=9.7×100=970；（3）4.8×7.8+78×0.52=4.8×7.8+7.8×5.2=（4.8+5.2）×7.8=10×7.8=78；（4）3.65×10.1=3.65×（10+0.1）=3.65×10+3.65×0.1=36.5+0.365=36.865． 38．【解答】解：①12.36﹣6.49﹣3.51=12.36﹣（6.49+3.51）=12.36﹣10=2.36；②8.5×3.8+8.5×6.2=8.5×（3.8+6.2）=8.5×10=85；③17.3×0.25×8=17.3×（0.25×8）=17.3×2=34.6；④15.32﹣1.8×5﹣3.46=15.32﹣9﹣3.46=6.32﹣3.46=2.86；⑤199×2.6=（200﹣1）×2.6=200×2.6﹣1×2.6=520﹣2.6=517.4；⑥3.6÷[（1.3+0.6）×5]=3.6÷[1.9×5]=3.6÷9.5=． 39．【解答】解：（1）8.5+6.85﹣6.35=8.5+（6.85﹣6.35）=8.5+0.5=9；（2）3.9+0.1﹣3.9+0.1 =（3.9﹣3.9）+（0.1+0.1）=0+0.2=0.2；（3）12.6﹣（3.75+5.08）=12.6﹣8.83=3.77． 40．【解答】解：（1）6.09﹣9.13÷8.3=6.09﹣1.1=4.99（2）3.84×9.6+0.96×61.6 =（3.84+6.16）×9.6=10×9.6=96（3）4.86×99=4.86×（100﹣1）=4.86×100﹣4.86=486﹣4.86=481.14（4）5.68×4+4.32÷0.25=5.68×4+4.32×4=（5.68+4.32）×4=10×4=40（5）6.4×4.5+3.6×4.5=（6.4+3.6）×4.5=10×4.5=45 41．【解答】解：①10.5+61×18=10.5+1098=1108.5 ②（3.14+12.6）÷8=15.74÷8=1.9675③4.5÷（15÷3）=4.5÷5=0.9④75+448÷4×19=75+112×19=75+2128=2203 42．【解答】解：（1）（18.5×3.8+3.8×2.5）÷0.19 =3.8×（18.5+2.5）÷0.19 =3.8×21÷0.19=3.8÷0.19×21=200×21=4200（2）[32﹣（7.25+0.75×8）]÷50=[32﹣（7.25+6）]÷50=[32﹣13.25]÷50=18.75÷50=0.375 43．【解答】解：①25.32﹣（3.4﹣1.2）=25.32﹣2.2=23.12②12﹣0.62﹣4.38=12﹣（0.62+4.38）=12﹣5=7 44．【解答】解：（1）5.12+2.54+4.88=5.12+4.88+2.54=10+2.54=12.54；（2）12.5×17.8×0.8=12.5×0.8×17.8=10×17.8=178；（3）0.24×0.48×4=0.1152×4=0.4608；（4）9.9×2.5=（10﹣0.1）×2.5=10×2.5﹣0.1×2.5=25﹣0.25=24.75；（5）9.4×5.8+10.6×5.8=（9.4+10.6）×5.8=20×5.8=116；（6）0.66×101=0.66×（100+1）=0.66×100+0.66×1=66+0.66=66.66；（7）4.8×0.25=（1.2×4）×0.25=1.2×（4×0.25）=1.2×1=1.2；（8）2.33×0.5×4 =2.33×（0.5×4）=2.33×2=4.66；（9）1.3×2.5+0.7×2.5=（1.3+0.7）×2.5=2×2.5=5；（10）1.26×0.6+1.26×0.4=1.26×（0.6+0.4）=1.26×1=1.26；（11）102×0.55=（100+2）×0.55=100×0.55+2×0.55=55+1.1=56.1；（12）0.034×0.5×0.2=0.034×（0.5×0.2）=0.034×0.1=0.0034． 45．【解答】解：（1）13.38+0.98=13.38+（1﹣0.02）=13.38+1﹣0.02=14.38﹣0.02=14.36；（2）7.02﹣2.98 =7.02﹣（3﹣0.02）=7.02﹣3+0.02 =4.02+0.02=4.04；（3）6.57﹣（0.68﹣0.39+0.32）=6.57﹣（0.68+0.32﹣0.39）=6.57﹣（1﹣0.39）=6.57﹣0.61=5.96；（4）13.8÷（1.38×0.2）=13.8÷1.38÷0.2=10÷0.2=50；（5）30.7﹣0.12×2﹣0.76=30.7﹣0.24﹣0.76=30.7﹣（0.24+0.76）=30.7﹣1=29.7；（6）7.8×1.01=7.8×（1+0.01）=7.8×1+7.8×0.01=7.8+0.078=7.878；（7）18.4﹣6.5+1.6+3.5 =（18.4+1.6）﹣（6.5﹣3.5）=20﹣3=17；（8）7.8÷0.6+7.8÷0.4=13+19.5=32.5；（9）12.13+7.5﹣1.13+2.85=（12.13﹣1.13）+（7.5+2.85）=11﹣10.35=0.65；（10）0.125×8.8=0.125×（8+0.8）=0.125×8+0.125×0.8=1+0.1=1.1；（11）9.4×3.2+6×0.32=9.4×3.2+0.6×3.2=（9.4+0.6）×3.2=10×3.2=32；（12）9.6×3.6+7.2×0.2=9.6×3.6+3.6×2×0.2=9.6×3.6+3.6×0.4=（9.6+0.4）×3.6=10×3.6=36． 46．【解答】解：（1）96÷（100×0.48）=96÷48=2；（2）3.6÷（1.2+0.5）×6=3.6÷1.7×6=×6=；（3）（967﹣31）÷（17+48）=936÷65=14.4；（4）72×10.1+27×10.1=（72+27）×10.1=99×10.1=99×（10+0.1）=99×10+99×0.1=990+9.9=999.9． 47．【解答】解：（1）3.4×7.8÷3.9=26.52÷3.9=6.8；（2）54÷（3.94+6.86）=54÷10.8=5． 48．【解答】解：①0.486+0.01+3.99 =0.486+（0.01+3.99）=0.486+4=4.486 ②17.5×2.3﹣7.5×2.3 =2.3×（17.5﹣7.5）=2.3×10=23 ③1.25×11×4×0.8=（1.25×0.8）×（11×4）=1×44=44④4.8×39+61×4.8=4.8×（39+61）=4.8×100=480⑤45.55﹣（6.82+15.55）=45.55﹣6.82﹣15.55=45.55﹣15.55﹣6.82=30﹣6.82=23.18⑥3.2×99+3.2=3.2×（99+1）=3.2×100=320⑦2.5×56+4.5×56 =56×（2.5+4.5）=56×7=392⑧（31.6﹣11.7）÷2.5÷4 =19.9÷（2.5×4）=19.9÷10=1.99⑨3.6×0.9+3.6×0.1=3.6×（0.9+0.1）=3.6×1=3.6 49．【解答】解：（1）7.5﹣2.4÷0.8×2.5 =7.5﹣3×2.5=7.5﹣7.5=0；（2）12.5×17+83×12.5=12.5×（17+83）=12.5×100=1250；（3）399×2.5=（400﹣1）×2.5=400×2.5﹣2.5=1000﹣2.5=997.25；（4）25÷（2.5÷0.4）=25÷2.5×0.4=10×0.4=4；（5）3.25×67+5.75×67+67 =（3.25+5.75+1）×67=10×67=670；（6）230÷2.5×7.5=92×7.5=690；（7）6.3+0.84+3.7+8.16=（6.3+3.7）+（0.84+8.16）=10+9=19；（8）100﹣（2.72+10.8）÷0.2=100﹣13.52÷0.2=100﹣67.6=32.4． 50．【解答】解：（1）0.25×3.25×4=0.25×4×3.25=1×3.25=3.25（2）6.72+3.2÷2.5=6.72+1.28=8（3）21.36÷0.4﹣23.4=53.4﹣23.4=30（4）0.8×4.5+1.2×4.5=（0.8+1.2）×4.5=2×4.5=9 。
小数除法脱式运算+简算260道含答案,推荐文档
小数除法脱式运算+简算260道一 .计算题（共50小题）1.用你喜欢的方法计算.32 X 12.5X 0.25 6.1 X 4.2+5.8X 6.1 1.7- 2.5- 0.4 16.1 - 4.2 - 5.8.3.脱式计算4.8- (1.2- 0.5) 12.8 - 12.8-5 71.4- (7 X 6)4.用你喜欢的方法计算0.65 X 101 - 0.65 12.6-3.25+6.756.35-0.2-0.5 5.7X 1.2- 19 1.25X 3.63X 0.8.5.我能用喜欢的方法计算下面各题.0.11 X 1.8+8.2X 0.11 3.5— 3.5X 0.98 0.75X 18-0.15 0.25X 4.78X 8.6 .能简算的要简算.17.3-0.125-8 14.72X 0.7+5.28X 0.73.5-0.56 8.5X 9.9+0.82.7.递等式计算，有简便运算的用简便方法38.75 - (24.5+8.75) 0.4X 2.32X 0.25 0.75X 101 4.2- 3.2X 0.97.56 X70.3- 17.48-7.6 3.64-5.2 X 23.3 21.8-0.8 - 1.2X 5 99+7.5645 - (5.25-0.25) 16.5X 101 - 16.5 0.96-0.3X 14 1.25X 4X 2.5X 8 36.45- (0.82+3.4X 0.2) 9.07-2.64-0.4 1.5X 101 12.6X 7.5+8.3 13.6X 0.85- 3.6X 0.85 104X 8.5 86.4-6.4 - 0.4 0.25X 6.2X 0.423 X 6.5+17 X36+0.4 X 0.25 (24.6— 18.1) X3.4 7.6X 9.9+7.6X 0.1 6.513.6X 0.8X 12.5 23.9X 8.5 - 3.9X 8.5 (2.55+9.6- 16) -0.42 9.2- 0.25-40.75X 4X 0.25X 49. 脱式计算（能简算的要用简算）10. 脱式计算，能简算的要简算 0.25 X 1.25X 1618.9- 18.9- 1.4 8.37X 1.2 - 8.37 X 0.243 X 11.8+5.7X 118.11. 用简便方法计算. 6.2+5.18+2.815.35- (5.35+7.2)12. 脱式计算，能简算的要简算. 0.7X 101 - 0.70.125X 4.95X 83.63 - 1.25+17.37 - 8.7551.72 - 8.66 - 1.34.4.536- 0.8+ 142.8 X3.6+1.4X 2.8 6.3X 10.1.4.2X 7.8+2.2X 4.29.5X 101(8 X 3.82) X1.250.125X 720.6X 3.9X 0.8 42 X 0.39+4.2X 6.112.9- 1.68 - 2.32 567- 20- 5.20.16- 7.2+9.814. 脱式计算：能简算的要简算16. 脱式计算.1.2X 0.25+2.8 X 0.25178.8- (26.4— 5.6)0.2X 0.6X 0.5X 4(7.5— 2.3X 0.4) -0.0115.89- (5.89+6.98)0.25X 13.7X 0.432.7X 28+7.3X 2815X 9.4 - 42 4.9+12.87-5.38 0.05X 0.7X 20 X 1.7.15. 计算下面各题, 能简算的要简算.5.04 X 28(15.4— 7.8) X 3.53.2X4.6+3.2X5.40.25 X 17.4X 420 - 6.72 - 3.28 8.33+7.45+1.67+2.553.6- 1.28+3.093.82+2.9+0.18+9.1 9.43 - (6.28 —1.57)21.32- (6.32+8.3) 13.75- (3.75+6.48) 15 - 7.35- 2.6518. 混合运算，能简便就简便19.81 - 2.68—8.32 5.6+6.6— 5.6+6.6 0.81 X 27+0.19X 27 101 X 0.19 -0.19.19. 用简便方法计算9.08 - 1.76— 4.24 18.38 - (5.38+1.8) - 8.2 17.45- (8.76— 6.55) 12.87+3.98- 3.87.20. 脱式计算，能简便的用简便方法计算.10.8- (3.94+6.86) X 0.8 0.65X 201 12.5X 3.9X 0.839.8 X 0.25X 4 37.6X 8+37.6X 2 0.78 X 99+0.78.21.8 -7.22 - 2.78 9- 0.24- 1.6X 1.1 9.12+9.12X 9 -6.02 45.2X 66.7+66.7X 53.8+66.7 0.25X 0.8X 0.125X 0.4 12.75- [14.6 - (1.3+8.2)]0.125X 36X (4- 0.5) -36 [ (6.1 — 4.6) X 0.8 - 1] X 0.36 15.6 - (4.1+0.2+6.86-0.7)[5- (1- 1.2X 0.8) ] - 4 1-0.25+0.4X 0.6 13.6X 3-40.6- 225.8+10.5- (5 - 3.5) 1.42 - 0.36- 6 X 0.6 49.5 X 0.2 - 2.07+ 23 6.7+3.3-4.4+5.622. 计算下面各题(能简算的要简算)50X (0.8+0.4) 7.34X 2.1+7.34X 6.8+7.34X 1.120.5- 1.25+ 0.8 9.88X 9+9.88.23. 计算下列各题(能用简便算法的要用简便算法).12.6- (1.02+3.18) 5.7X 6.9+4.3X 6.9(0.81+2.7) -0.9 [ (8.4— 7.9) - 0.25] X 1.2.25. 能简算的用简便方法计算.(写出主要简便过程，无过程不得分)1.6X 3.9X 1.25 4.87X2.34+48.7 X 0.2662.5X3.2X 12.5 3.95X 7.6+3.95X 3.4 - 3.95.26. 计算下面各题，能简算的要简算7.8X 6.9+2.2X 6.9 2.36X 2.5X 4 102X 0.454.19X 99+4.19 21.36-0.8- 12.9 3.2+ 0.8X 0.2627. 计算(能简算的要简算).6.33 X 101 - 6.33 1.6X 55.4 - 55.4X 0.6 17.68-5.2+2.7X 1.5 (1.1— 0.78) X ( 2.7— 1.95) 35.6 - 5X 1.73 15-0.2-2.528. 脱式计算(能简算的要简算)2.5X 1.37X 0.4 4.8X 0.25X 25 0.89X 4.8+0.89X 5.2101X 0.78X 20 8.8X 1.25X 15 4.3X 0.8X 529. 计算下面各题，能简算的要简算.44.28- 0.9-4.1 0.25X 0.39X 4 7.6+7.6 X 999.07 - 22.78-3.4 4.8X 99+4.8 30.下面各题，能简算的就要简算. 5.8+3.8X 0.25 1.7X (4.65 — 3.87) 6.3X 10.11.25X 4.3X 0.84.5X 102 0.54X 101 - 0.54 3.4X 2.5+6.6X 2.5.31. 计算下列各题. 0.45X 12X 0.2 2.8-2.8X 0.15 10-6.06+8.5 32. 用简便方法计算. 0.25 X 9.87X 4 6.2X 2.1 - 2.1 0.9X 0.8X 1000.73 X 1022.8X 1.43+0.57 72X 0.81+10.36X 0.25X 1.8 7.06X 2.4-5.836.2X 1.8+13.8X 1.8 0.125X 2.3X 8(6.8+2.6) X 5 0.23X 98.33.能用简便方法的用简便方法计算 12.5X 32X 2.5 6.8 X 9.9第8页(共19页)7.2- [1.8X (3.4 — 2.9)].34. 用你喜欢的方法计算.3.4X 9+3.4 6.4-0.8 - 1.5X 4 3.78- 0.25-4 17-[ (1.2+0.5) X 5].35. 用你喜欢的方法计算2.5X 1.25X 8X 0.4 12.8X 1.7+87.2X 1.7 100 - 4.35- 5.65.36. 用递等式计算(能简算的要简算).4+7.6X 15 26.08+ 0.25-4 19.7+ (80.5-35 X 0.2)37. 计算，能简算的要简算.1.25X2.25X 0.8 9.7X 99+9.7 4.8X 7.8+78X 0.523.65X 10.1.38 .计算下面各题.(能简算的用简便算法)① 12.36-6.49- 3.51 ②8.5X 3.8+8.5X 6.2 ③ 17.3X 0.25X 8④ 15.32- 1.8X5 - 3.46 ⑤ 199X 2.6 ⑥3.6-[ (1.3+0.6) X 5]39. 计算8.5+6.85 - 6.35 3.9+0.1 - 3.9+0.1 12.6- (3.75+5.08)40. 计算，能简算的要简算6.09 - 9.13-8.3 3.84X 9.6+0.96X 61.6 4.86X 995.68 X 4+4.32- 0.256.4X 4.5+3.6X 4.5.41. 脱式计算.10.5+61 X 18 (3.14+12.6) -8 4.5- (15-3) 75+448-4X 19.42. 计算：(18.5X 3.8+3.8X 2.5) -0.19 [32 - ( 7.25+0.75X 8) ] - 50.43. 脱式计算，能简算的就简算：25.32- (3.4— 1.2) 12- 0.62- 4.38.44. 用简便方法计算下面各题.5.12+2.54+4.88 12.5X 17.8X 0.8 0.24X 0.48X 4 9.9X 2.59.4X 5.8+10.6X 5.8 0.66X 101 4.8X 0.25 2.33X 0.5X 4 1.3X 2.5+0.7X 2.5 1.26X 0.6+1.26X 0.4 102X 0.55 0.034X 0.5X 0.245. 计算.(怎样简便就怎么计算)13.38+0.98= 7.02— 2.98 6.57 - (0.68 — 0.39+0.32)13.8- (1.38X0.2) 30.7-0.12X 2-0.76 7.8X 1.0118.4-6.5+1.6+3.5 7.8-0.6+7.8+ 0.4 12.13+7.5 - 1.13+2.850.125X 8.8 9.4X 3.2+6 X 0.32 9.6X 3.6+7.2X 0.2.46. 计算下面各题，能简算得要简算.96- (100X 0.48) 3.6- (1.2+0.5) X 6(967— 31) + ( 17+48) 72 X 10.1+27X 10.1.47. 用自己喜欢的方法计算.3.4X 7.8-3.9 48. 用简便方法计算6.3+0.84+3.7+8.16 100- (2.72+10.8) -0.2 50. 脱式计算0.25X 3.25X 4 6.72+3.2-2.5 21.36- 0.4— 23.4 0.8X 4.5+1.2X 4.5.54 - (6.86+3.94)0.486+0.01+3.99 17.5X 2.3- 7.5X2.3 1.25X 11 X 4 X 0.84.8X 39+61 X 4.8 45.55 - (6.82+15.55) 3.2X 99+3.22.5X 56+4.5X 56 (31.6— 11.7) -2.5-43.6X 0.9+3.6X 0.149. 计算下列各题. （能简算的要简算） 7.5-2.4-0.8X 2.5 12.5X 17+83X 12.5 399X 2.5 25- (2.5- 0.4) 3.25X67+5.75X 67+67 230- 2.5X 7.5小数除法脱式运算+简算260道参考答案与试题解析一.计算题(共50 小题)1.【解答】解：(1) 32X 12.5X 0.25=4X 8X 12.5X 0.25=(4X 0.25) X (8X 12.5) =1X 100=100(2) 6.1X 4.2+5.8X6.1=6.1X (4.2+5.8) =6.1 X 10=61(3) 1.7 士2.5 士0.4=1.7+ (2.5X 0.4) =1.7 士1=1.7 (4) 16.1 - 4.2 — 5.8=16.1- (4.2+5.8) =16.1- 10=6.1 2.【解答】解：(1) (0.6X 0.8+0.12) - 1.2=0.6 士1.2=0.5 答：商是0.5. (2) (14.81+5.19) X ( 14.81 - 5.19) =20X 9.62=192.4 答：积是192.4. (3) [ (2.7+4.5) 士12] X 0.3=[7.2士12] X 0.3=0.6X 0.3=0.18答：积是0.18. 3.【解答】解：①4.8士(1.2士0.5) =4.8士2.4=2②12.8- 12.8-5=12.8-2.56=10.24®71.4- (7X 6) =71.4士7士6=10.2士6=1.7 4.【解答】角车：①0.65 X 101 - 0.65 =0.65X ( 101 - 1) =0.65X 100=65® 12.6-3.25+6.75=12.6+ (6.75 —3.25) =12.6+3.5=16.1③6.35士0.2士0.5=6.35士(0.2X 0.5) =6.35士0.1=63.曜5.7X 1.2- 19 =5.7士19X 1.2=0.3X 1.2=0.36® 1.25X3.63X 0.8=( 1.25X 0.8) X 3.63=1 X 3.63=3.63 5.【解答】解：① 0.11X 1.8+8.2 X 0.11=0.11X ( 1.8+8.2) =0.11 X 10=1.1 ②3.5 - 3.5X 0.98=3.5X ( 1- 0.98) =3.5 X 0.02=0.07®0.75X 18士0.15=0.75士0.15X 18=5X 18=90®0.25X4.78X 8=0.25X 8X4.78=2X4.78=9.56 6.【解答】解：① 17.3士0.125-8 =17.3士(0.125X8)=17.3士1=17.3 ② 14.72X 0.7+5.28X 0.7= (14.72+5.28) X 0.7=20X 0.7=14③ 3.5 士0.56 = ( 3.5 士0.7)士( 0.56 士0.7 ) =5 士8=0.625④ 8.5 X 9.9+0.82=8.5 X ( 10 - 0.1 ) +0.82=8.5 X 10 - 8.5 X 0.1+0.82=85 - 0.85+0.82=85-(0.85 - 0.82) =85- 0.03=84.97 7.【解答】解：(1) 38.75-(24.5+8.75) =38.75- 24.5 - 8.75=38.75- 8.75 - 24.5=30 - 24.5=5.5; (2) 0.4 X 2.32 X 0.25=0.4X 0.25X 2.32=0.1 X 2.32=0.232; (3) 0.75X 101=0.75X (100+1) =0.75 X 100+0.75 X 1=75+0.75=75.75; (4) 4.2 - 3.2 X 0.9=4.2- 2.88=1.32; (5) 7.56X 99+7.56=7.56X (99+1) =7.56X 100=756; (6) 70.3- 17.48士7.6=70.3-2.3=68;(7) 3.64士5.2X 23.3=0.7X 23.3=16.31; (8) 21.8士0.8 - 1.2X 5=27.25— 6=21.25; (9) 45- (5.25-0.25) =45+ 21毛；(10) 16.5X 101 - 16.5=16.5X (101 - 1) =16.5X 100=1650;(11) 0.96- 0.3X 14=3.2X 14=44.8; (12) 1.25X 4 X 2.5X 8= (1.25X 8) X ( 4 X 2.5) =10X 10=100； ( 13) 36.45- ( 0.82+3.4X 0.2) =36.45 士(0.82+0.68) =36.45士 1.5=24.3; (14) 9.07-2.64士0.4=9.07—6.6=2.47; (15) 1.5 X 101=1.5 X ( 100+1 ) =1.5 X 100+1.5 X 1=150+1.5=151.5; ( 16) 12.6 X 7.5+8.3=94.5+8.3=102.8; (17) 13.6X 0.85 - 3.6X 0.85= (13.6 - 3.6) X 0.85=10X 0.85=8.5; (18) 104X 8.5= (100+4) X8.5=100X 8.5+4 X 8.5=850+34=884;(19) 86.4 士 6.4 - 0.4=13.5 - 0.4=13.1; ( 20) 0.25X 6.2 X 0.4=0.25 X 0.4 X 6.2=0.1 X 6.2=0.62; (21) 23X 6.5+17X 6.5= (23+17) X 6.5=40X 6.5=260; (22) 36士0.4 X 0.25=90X 0.25=22.5; (23) (24.6- 18.1) X 3.4=6.5X 3.4=22.1; (24) 7.6X 9.9+7.6 X 0.1=7.6X (9.9+0.1) =7.6X 10=76; (25) 13.6X 0.8X 12.5=13.6X (0.8X 12.5) =13.6X 10=136; (26) 23.9X 8.5 - 3.9X 8.5= (23.9 - 3.9) X 8.5=20X 8.5=170; (27) (2.55+9.6士16) 士0.42= (2.55+0.6) 士0.42=3.15士0.42=7.5; (28) 9.2士0.25士4=9.2士(0.25X4) =9.2- 1=9.2.8.【解答】解：(1) 0.75X4X 0.25X 4= (0.75X 4) X (0.25X 4) =3X 1=3 (2) 9.6+9.9X 99=9.6+9.9X (100 - 1) =9.6+9.9X 100 -9.9=9.6+990- 9.9=989.7 (3) 15.58士8.2- 0.72=1.9— 0.72=1.18 (4) 4.536士0.8 士14=5.67士14=0.405 (5) 2.8X 3.6+1.4X2.8=2.8X ( 3.6+1.4) =2.8X 5=14 (6) 6.3X10.1=6.3X (10+0.1) =6.3X 10+6.3x 0.1=63+0.63=63.63 9.【解答】解：(1) 4.2X 7.8+2.2X 4.2 =4.2X (7.8+2.2 ) =4.2X 10=42 (2) 9.5X 101=9.5X ( 100+1) =9.5X100+9.5=950+9.5=959.5 (3) (8X 3.82) X 1.25 = (8X 1.25) X3.82=10X 3.82=38.2 (4) 0.125X 72=0.125X 8 X 9=1 X 9=9 ( 5) 0.6X 3.9X 0.8 =2.34X 0.8=1.872( 6) 42 X 0.39+4.2X 6.1=42X 0.39+42 X 0.61=42X (0.39+0.61) =42X 1=42 10.【解答】解：(1)0.25 X 1.25X 16=0.25X 1.25X (2X 8) = (0.25X 2) X (1.25 X 8) =0.5X 10=5(2) 18.9- 18.9士1.4=18.9— 13.5=5.4 (3) 8.37X 1.2 - 8.37X 0.2=8.37X (1.2 - 0.2) =8.37X 1=8.37(4) 43 X 11.8+5.7 X 118=43X 11.8+57X 11.8= (43+57) X 11.8=100 X 11.8=1180 11 .【解答】解：(1 ) 6.2+5.18+2.8=6.2+2.8+5.18 =9+5.18=14.18 (2) 15.35 - (5.35+7.2) =15.35— 5.35 - 7.2=10-7.2=2.8(3) 3.63 - 1.25+17.37-8.75=(3.63+17.37) - (1.25+8.75) =21 - 10=11(4) 51.72 - 8.66 - 1.34=51.72- (8.66+1.34) =51.72 - 10=41.72 12 .【解答】解：(1) 0.7X 101 - 0.7 =0.7X (101 - 1) =0.7X 100=70(2) 0.125X 4.7X 8=0.125X 8X 4.7=1 X 4.7=4.7(3) 12.9 - 1.68- 2.32 =12.9- (1.68+2.32)=12.9- 4=8.9 (4) 567士20-5=567- (20X 5) =567士100=5.67 13.【解答】解：① 20.16 士7.2+9.8 =2.8+9.8=12.6 ; ② 6.2 X 2.7+6.5 X 7.3=16.74+47.45=64.19 ; ③ 32.8+9.6+7.2=9.6+ ( 32.8+7.2 )=9.6+40=49.6. 14.【解答】解：(1) 15.89- (5.89+6.98) =15.89- 5.89- 6.98=10-6.98=3.02; (2) 0.25X 13.7X 0.4=0.25X 0.4X 13.7=0.1X 13.7=1.37; (3) 32.7X 28+7.3X 28 = (32.7+7.3) X 28=40X 28=1120; (4) 15X 9.4 - 42=141 - 42=99; (5) 4.9+12.87- 5.38=17.77- 5.38=12.39; (6) 0.05 X 0.7 X 20X 1.7=0.05X 20X 0.7X 1.7=1 X 0.7X 1.7=0.7X 1.7=1.19.15.【解答】解：(1) 5.04X 28= (5+0.04) X28=5 X 28+0.04 X 28=1401.12=141.12; (2) (15.4 - 7.8) X 3.5 =7.6 X 3.5=26.6; (3) 3.2X4.6+3.2X 5.4=3.2X (4.6+5.4) =3.2X 10=32; (4) 0.25X 17.4X 4=0.25X 4X 17.4=1 X 17.4=17.4; (5) 20- 6.72- 3.28=20- ( 6.72+3.28) =20- 10=10; (6) 8.33+7.45+1.67+2.55=8.33^1.67+7.45+2.55=(8.33+1.67) +(7.45+2.55) =10+10=20. 16.【解答】解：(1) 0.2X 0.6X 0.5X4 = (0.2X 0.5) X (0.6X4)=0.1 X 2.4=0.24; (2) (7.5 - 2.3X 0.4) 士0.01 = 7.5 - 0.92) 士0.01=6.58士0.01=658; (3) 1.2 X 0.25+2.8 X 0.25 = ( 1.2+2.8) X 0.25=4 X 0.25=1;(4) 178.8- ( 26.4— 5.6) =178.8士20.8^^ . 17.【解答】解：(1) 3.6 -521.28+3.09=2.32+3.09=5.41(2) 3.82+2.9+0.18+9.1 =(3.82+0.18) +(9.1+2.9) =4+12=16 (3) 9.43- (6.28- 1.57) =9.43+1.57- 6.28=11 - 6.28=4.72(4) 21.32- (6.32+8.3) =21.32-6.32 - 8.3=15-8.3=6.7 (5) 13.75- (3.75+6.48) =13.75- 3.75- 6.48=10 -6.48=3.52(6) 15- 7.35-2.65=15- (7.35+2.65) =15- 10=5 18.【解答】解：① 19.81 - 2.68 - 8.32=19.81 -(2.68+8.32) =19.81 - 11=8.81 ②5.6+6.6 - 5.6+6.6= (5.6-5.6) + (6.6+6.6)=0+13.2=13.2®0.81 X 27+0.19X27=27X (0.81+0.19) =27X 1=27® 101 X 0.19-0.19=(101- 1) X 0.19=100X 0.19=19 19.【解答】解：(1 ) 9.08 - 1.76 - 4.24 =9.08 - ( 1.76+4.24 ) =9.08 - 6=3.08 ;(2) 18.38- (5.38+1.8) - 8.2=18.38- 7.18- 8.2=11.2- 8.2=3; (3) 17.45— (8.76 -6.55) =17.45- 8.76+6.55=17.45+6.55 - 8.76=24- 8.76=15.24; (4) 12.87+3.98- 3.87=12.87- 3.87+3.98=9+3.98=12.98. 20.【解答】解：① 10.8- (3.94+6.86) X0.8 =10.8士 10.8X 0.8=1 X 0.8=0.8②0.65X 201 =0.65X (200+1) =0.65 X 200+0.65 X 1=130+0.65=130.65® 12.5X 3.9X 0.8=12.5X 0.8X 3.9=10X 3.9=39® 39.8 X 0.25X 4 =39.8X ( 0.25X 4) =39.8X 1=39.8⑤37.6X 8+37.6X 2 =37.6X (8+2) =37.6 X 10=376 ⑥ 0.78X 99+0.78=0.78X ( 99+1 ) =0.78 X 100=7821.【解答】 解：(1) 21.8-7.22- 2.78=21.8- (7.22+2.78) =21.8- 10=11.8 (2) 9 - 0.24士 1.6X1.1=9- 0.15X 1.1=9- 0.165=8.835 (3) 9.12+9.12X 9 - 6.02=9.12 X ( 1+9) - 6.02=9.12X 10 - 6.02=91.2 - 6.02=85.18 ( 4 ) 45.2 X 66.7+66.7 X 53.8+66.7= (45.2+53.8+1) X 66.7=100X 66.7=6670 (5) 0.25X 0.8X 0.125X 0.4=(0.25X 0.4) X (0.125X 0.8) =0.1 X 0.1=0.01(6) 12.75士 [ 14.6- (1.3+8.2) ] =12.75 士 [14.6 - 9.5] =12.75-5.1=2.5 (7) 0.125X 36X (4士0.5) 士36=0.125X (4士0.5) X (36士36) =0.125X 8X 1=1 (8) [ (6.1 — 4.6) X 0.8 — 1] X 0.36=[1.5X 0.8 - 1] X 0.36=[ 1.2 - 1] X 0.36=0.2 X 0.36=0.072 (9) 15.6 - (4.1+0.2+6.86- 0.7) =15.6 -(4.1+0.2+9.8) =15.5— (4.1+10) =15.5- 14.1=1.4 (10) [5- (1 - 1.2X 0.8)] 士 4=[5 - ( 1 - 0.96) ] 士 4=[5 - 0.04] 士 4=4.96 士 4=1.24(11) 1 士 0.25+0.4 X 0.6=4+0.24=4.24 (12) 13.6X 3-40.6士 2=40.8— 20.3=20.5 (13) 25.8+10.5士 ( 5 -3.5) =25.8+10.5士 1.5=25.8+7=32.8 (14) 1.42- 0.36士6X 0.6=1.42— 0.36=1.07(15 ) 49.5 X 0.2 - 2.07 士 23=9.9 - 0.09=9.81 ( 16 ) 6.7+3.3 士4.4+5.6=6.7+0.75+5.6=7.45+5.6=13.05 22.【解答】 解：① 50 X (0.8+0.4) =50X 0.8+50 X 0.4=40+20=60®7.34 X 2.1+7.34X 6.8+7.34X 1.1=7.34X ( 2.1+6.8+1.1) =7.34 X 10=73.4 ③ 20.5 士 1.25 士 0.8=20.5 士 ( 1.25 X 0.8 ) =20.5 士 1=20.5 ④9.88X 9+9.88=9.88X ( 9+1) =9.88X 10=98.8 23.【解答】 解：(1) 12.6士 (1.02+3.18) =12.6士 4.2=3; (2) 5.7X 6.9+4.3X 6.9= (5.7+4.3) X 6.9=10X 6.9=69;(3) (0.81+2.7) -0.9=3.51- 0.9=3.9; (4) [ (8.4— 7.9) - 0.25] X 1.2=[0.5- 0.25] X1.2=2X1.2=24 24.【解答】 解：(1) 25 X 1.25X 32 =25X 1.25X 8X 4= (25X 4) X (1.25X8) =100X 10=1000 (2)(=金)x 35^ X 35毫 X 35=10+7=1725.【解答】解：(1) 1.6X3.9X 1.25=0.8X2X3.9X 1.25= (0.8X 1.25)X (2X 3.9) =1X 7.8=7.8(2) 4.87X2.34+48.7X 0.266=4.87X2.34+4.87X2.66=4.87 X(2.34+2.66) =4.87X 5=24.35 (3) 0.49 X 9.9 =0.49X ( 10- 0.1) =0.49X 10- 0.49X 0.1=4.9- 0.049=4.851 (4) 0.05X 0.7X 20X 1.7= (0.05X 20) X (0.7X 1.7) =1X 1.19=1.19 (5)2.5X3.2X 12.5 =2.5X0.4X 8X 12.5 = (2.5X0.4) X (8X12.5) =1X 100=100(6) 3.95X7.6+3.95X 3.4- 3.95=3.95X (7.6+3.4- 1) =3.95X 10=39.5 26.【解答】 解：(1)7.8X6.9+2.2X6.9= (7.8+2.2) X6.9=10X6.9=69 (2) 2.36 X 2.5X 4=2.36X (2.5X 4) =2.36X 10=23.6 (3) 102X 0.45= (100+2) X 0.45=100 X 0.45+2X 0.45=45+0.9=45.9 (4) 4.19X 99+4.19=4.19X (99+1) =4.19X 100=419 (5)21.36士0.8 - 12.9=26.7- 12.9=13.8(6)3.2士0.8X 0.26=4X 0.26=1.04 27.【解 答】解：(1) 6.33X 101 - 6.33=6.33X (101 - 1) =6.33X 100=633; (2) 1.6X 55.4 -55.4 X 0.6= ( 1.6 - 0.6 ) X 55.4=1 X 55.4=55.4; ( 3 ) 17.68 士5.2+2.7 X 1.5=3.4+4.05=7.45; (4) (1.1- 0.78) X (2.7- 1.95) =0.32X0.75=0.24; (5) 35.6 -5 X1.73=35.6 - 8.65=26.95; ( 6) 15 士 0.2 士2.5=15士(0.2 X 2.5) =15 士0.5=30. 28.【解答】 解：(1) 2.5X 1.37X 0.4=2.5X 0.4X 1.37=1 X 1.37=1.37;79(3) 78 X(79— 1) X —=79X(2) 4.8X 0.25X 25= (4X 4X 0.3) X 0.25X 25= (4X 0.25) X ( 4X 25) X 0.3=1 X 100X0.3=30; (3) 0.89X 4.8+0.89X 5.2=0.89X (4.8+5.2) =0.89X 10=8.9; (4) 101X 0.78X 20=101 X (0.78X 20) =101 X 15.6= (100+1) X 15.6=100X 15.6+1 X 15.6=1560+15.6=1575.6; (5) 8.8X 1.25X 15= (8 X 1.1) X 1.25X 15=(8 X 1.25) X (1.1 X 15) =10 X 16.5=165; ( 6 ) 4.3 X 0.8 X 5=4.3 X ( 0.8 X 5) =4.3 X 4=17.2. 29.【解答】解：(1) 44.28-0.9-4.1=49.2+4.1=12;(2) 0.25X 0.39X 4= (0.25X 4) X 0.39=1 X 0.39=0.39; (3) 7.6+7.6 X 99=7.6X ( 1+99) =7.6X 100=760; (4) 9.07-22.78士3.4=9.07- 6.7=2.37; (5) 4.8X 99+4.8=4.8X (99+1) =4.8 X 100=480 ; ( 6 ) 6.3 X 10.1=6.3 X ( 10+0.1 ) =6.3 X 10+6.3 X 0.1=63+0.63=63.63. 30.【解答】解：(1) 5.8+3.8X 0.25=5.8+0.95=6.75 (2) 1.7X (4.65-3.87) =1.7X 0.78=1.326 (3) 1.25X 4.3X 0.8=1.25X 0.8X 4.3=1 X 4.3=4.3(4) 4.5X 102=4.5X ( 100+2) =4.5X 100+4.5X 2=450+9=459 (5) 0.54X 101 - 0.54=0.54X (101- 1) =0.54X 100=54(6) 3.4X 2.5+6.6X 2.5= (3.4+6.6) X 2.5=10 X 2.5=25 31.【解答】解：① 0.45X 12 X 0.2=0.45X 0.2X 12=0.09X 12=1.08 ② 6.2X2.1 - 2.1 =2.1 X (6.2- 1) =2.1 X 5.2=10.92 ③0.9X 0.8X 100=0.72X 100=72 ④ 2.8 - 2.8 X 0.15 =2.8 X ( 1 - 0.15) =2.8 X 0.85=2.38 ⑤ 2.8 X 1.43+0.57 =4.004+0.57=4.574 ⑥72 X 0.81+10.3=58.32+10.3=68.62 ⑦10 -6.06+8.5=3.94+8.5=12.44 ⑧ 6 X 0.25 X 1.8 =1.5 X 1.8=2.7⑨7.06 X 2.4 - 5.8=16.944-5.8=11.144 32.【解答】解：(1) 0.25X 9.87X 4 =0.25X 4X 9.87=1X 9.87=9.87; (2) 36.2X 1.8+13.8X 1.8 = (36.2+13.8) X 1.8=50X 1.8=90; (3)0.125X 2.3X 8=0.125X 8 X2.3=1 X 2.3=2.3; (4) 0.73X 102 =0.73X (100+2) =0.73 X 100+0.73X 2=73+1.46=74.46; (5) (6.8+2.6) X 5 =6.8X 5+2.6X5=34+13=47; (6) 0.23 X 98=0.23X ( 100 — 2) =0.23X 100 -0.23X2=23-0.46=22.54. 33.【解答】解：(1) 12.5X 32X 2.5 =12.5X 4X 8X 2.5=(12.5X 8) X (2.5X 4) =100X 10=1000；(2) 6.8X 9.9 =6.8X (10-0.1)=6.8X 10- 6.8X 0.1=68— 0.68=67.32; (3) 7.2士[1.8X (3.4— 2.9) ] =7.2-[1.8X 0.5] =7.2- 0.9=8. 34.【解答】解：(1) 3.4X 9+3.4=30.6+3.4=34; (2) 6.4士0.8- 1.5X4=8- 6=2; (3) 3.78士0.25士4=3.78士(0.25X4) =3.78士1=3.78;(4) 17- [ (1.2+0.5) X5]=17士[1.7X 5] =17士8.5=2. 35.【解答】解：(1)2.5X 1.25X 8X 0.4 = (2.5X 0.4) X (1.25X 8) =1X 10=10； (2) 12.8X 1.7+87.2X 1.7 =( 12.8+87.2) X 1.7=100X 1.7=170; ( 3) 100 - 4.35 - 5.65=100-(4.35+5.65) =100- 10=90. 36.【解答】解：(1) 4+7.6X 15 =4+114=118; (2)26.08士0.25士4=26.08士(0.25X 4) =26.08士1=26.08; (3) 19.7+ (80.5士35X 0.2) =19.7+(2.3X 0.2) =19.7+0.46=20.16. 37.【解答】解：(1) 1.25X 2.25X 0.8=1.25X 0.8X 2.25=1 X 2.25=2.25; (2) 9.7X 99+9.7=9.7X (99+1) =9.7X 100=970; (3) 4.8X 7.8+78X 0.52=4.8X 7.8+7.8X 5.2= (4.8+5.2) X 7.8=10X 7.8=78; (4) 3.65X 10.1=3.65X (10+0.1) =3.65X 10+3.65X 0.1=36.5+0.365=36.865. 38.【解答】解：① 12.36-6.49 - 3.51=12.36- (6.49+3.51) =12.36- 10=2.36;②8.5X 3.8+8.5 X 6.2=8.5X (3.8+6.2) =8.5X 10=85;③ 17.3X 0.25X 8=17.3X ( 0.25X 8) =17.3 X 2=34.6;④ 15.32 - 1.8X 5 - 3.46=15.32- 9 -3.46=6.32- 3.46=2.86;⑤199X 2.6= (200— 1) X 2.6=200X 2.6 - 1 X2.6=520— 2.6=517.4;⑥3.6士[ (1.3+0.6) X 5] =3.6 -[1.9X 5]=3.6 士9.5理.39.【解答】解：(1) 8.5+6.85 - 6.35 =8.5+ (6.85- 6.35) =8.5+0.5=9; (2) 3.9+0.1 - 3.9+0.1 = (3.9-3.9) + (0.1+0.1) =0+0.2=0.2;(3) 12.6 - (3.75+5.08) =12.6— 8.83=3.77. 40.【解答】解：(1) 6.09 - 9.13士8.3=6.09— 1.1=4.99 (2) 3.84X 9.6+0.96X 61.6 = (3.84+6.16) X9.6=10X 9.6=96(3) 4.86X 99=4.86X (100- 1) =4.86X 100- 4.86=486- 4.86=481.14 (4) 5.68 X 4+4.32 士0.25 =5.68X 4+4.32X 4= (5.68+4.32) X4=10X 4=40 (5) 6.4X 4.5+3.6 X 4.5= ( 6.4+3.6 ) X 4.5=10 X 4.5=45 41 .【解答】解：① 10.5+61 X18=10.5+1098=1108.5 ②(3.14+12.6) 士8=15.74士8=1.9675^4.5士(15士3) =4.5士5=0.9®75+448士4X 19=75+112X 19=75+2128=2203 42.【解答】角牟：(1) (18.5X 3.8+3.8X 2.5) 士0.19 =3.8X (18.5+2.5) 士0.19 =3.8X 21 士0.19=3.8士0.19 X 21=200X 21=4200 (2) [32 - ( 7.25+0.75 X 8) ] 士50=[ 32 - (7.25+6) ] - 50=[32- 13.25] -50=18.75士50=0.375 43.【解答】解：① 25.32 -(3.4 - 1.2) =25.32-2.2=23.12® 12 - 0.62-4.38=12- (0.62+4.38) =12- 5=7 44.【解答】解：(1)5.12+2.54+4.88=5.12+4.88+2.54=10+2.54=12.54; (2) 12.5 X 17.8 X 0.8=12.5X 0.8 X 17.8=10 X 17.8=178; ( 3) 0.24 X 0.48 X 4=0.1152X 4=0.4608; (4) 9.9X2.5= (10- 0.1) X 2.5=10X2.5- 0.1 X2.5=25- 0.25=24.75;(5) 9.4X 5.8+10.6X 5.8= (9.4+10.6) X 5.8=20X 5.8=116; (6) 0.66X 101=0.66 X (100+1) =0.66X 100+0.66X 1=66+0.66=66.66; (7)4.8X 0.25= 1.2X 4) X 0.25=1.2 X (4 X 0.25) =1.2X 1=1.2; (8) 2.33X 0.5X 4 =2.33X (0.5X4) =2.33X 2=4.66;(9) 1.3 X 2.5+0.7X 2.5=( 1.3+0.7) X 2.5=2X 2.5=5 ; (10) 1.26X 0.6+1.26 X 0.4=1.26 X (0.6+0.4) =1.26X 1=1.26; (11) 102X 0.55= (100+2) X0.55=100X 0.55+2 X 0.55=55+1.1=56.1 ; ( 12 ) 0.034 X 0.5 X 0.2=0.034 X ( 0.5 X 0.2 ) =0.034 X 0.1=0.0034.45.【解答】解：(1) 13.38+0.98=13.38+( 1 - 0.02) =13.38+1 -0.02=14.38- 0.02=14.36; (2) 7.02- 2.98 =7.02- ( 3- 0.02) =7.02- 3+0.02 =4.02+0.02=4.04;(3) 6.57- (0.68 -0.39+0.32) =6.57- (0.68+0.32- 0.39) =6.57 -(1 - 0.39) =6.57— 0.61=5.96;(4) 13.8士(1.38X 0.2) =13.8士 1.38士0.2=10 士0.2=50; (5) 30.7 - 0.12X 2 -0.76=30.7— 0.24- 0.76=30.7— (0.24+0.76)=30.7- 1=29.7; (6) 7.8 X 1.01=7.8X (1+0.01) =7.8X 1+7.8 X 0.01=7.8+0.078=7.878;(7) 18.4-6.5+1.6+3.5 =(18.4+1.6) — (6.5— 3.5) =20— 3=17; (8)7.8士0.6+7.8士0.4=13+19.5=32.5; (9) 12.13+7.5 - 1.13+2.85= ( 12.13 - 1.13) + (7.5+2.85) =11 - 10.35=0.65; (10) 0.125X 8.8=0.125X (8+0.8) =0.125X 8+0.125 X 0.8=1+0.1=1.1; ( 11) 9.4 X 3.2+6 X 0.32 =9.4 X 3.2+0.6 X 3.2=(9.4+0.6) X 3.2=10X 3.2=32; (12) 9.6 X 3.6+7.2 X 0.2=9.6X 3.6+3.6X 2X 0.2=9.6X 3.6+3.6X 0.4= (9.6+0.4) X 3.6=10X 3.6=36. 46.【解答】解：(1) 96 士(100X 0.48) =96士48=2; (2) 3.6士(1.2+0.5) X 6=3.6士1.7 X 6辛X 6^^; (3) (967-31) 士( 17+48) =936+ 65=14.4; (4) 72X 10.1+27X 10.1 =(72+27 ) X 10.1=99 X 10.1=99 X ( 10+0.1 ) =99 X 10+99 X0.1=990+9.9=999.9. 47.【解答】解：(1) 3.4X 7.8- 3.9=26.52士3.9=6.8; (2)54- (3.94+6.86) =54- 10.8=5. 48.【解答】解：① 0.486+0.01+3.99 =0.486+(0.01+3.99) =0.486+4=4.486 ② 17.5X 2.3- 7.5X 2.3 =2.3X ( 17.5-7.5) =2.3 X 10=23 ③1.25X 11X 4X 0.8=(1.25X 0.8) X (11X 4) =1X 44=44®4.8X 39+61X 4.8=4.8X ( 39+61) =4.8 X 100=480 ⑤45.55 - ( 6.82+15.55) =45.55 - 6.82 一15.55=45.55- 15.55- 6.82=30- 6.82=23.18⑥3.2 X 99+3.2=3.2X ( 99+1) =3.2X 100=32C@2.5 X 56+4.5 X 56 =56 X (2.5+4.5) =56X 7=392® (31.6 - 11.7)- 2.5-4 =19.9+ (2.5X4) =19.9+ 10=1.99®3.6X 0.9+3.6X 0.1=3.6X (0.9+0.1) =3.6X 1=3.6 49.【解答】解：(1) 7.5- 2.4-0.8X2.5 =7.5— 3X 2.5=7.5— 7.5=0;(2) 12.5X 17+83X 12.5=12.5X ( 17+83) =12.5X 100=1250; (3) 399X 2.5 = (400- 1) X 2.5=400X2.5 - 2.5=1000-2.5=997.25; (4) 25- ( 2.5- 0.4) =25 -2.5X 0.4=10X 0.4=4; (5) 3.25X 67+5.75X 67+67 = (3.25+5.75+1) X 67=10 X 67=670; (6) 230+ 2.5X 7.5=92X 7.5=690; (7) 6.3+0.84+3.7+8.16= (6.3+3.7) + (0.84+8.16) =10+9=19; (8) 100- ( 2.72+10.8) -0.2=100- 13.52-0.2=100 -67.6=32.4. 50.【解答】解：(1) 0.25X 3.25X 4=0.25X 4X 3.25=1 X 3.25=3.25(2) 6.72+3.2- 2.5=6.72+1.28=8 (3) 21.36-0.4 - 23.4=53.4-23.4=30 (4) 0.8 X 4.5+1.2X 4.5= (0.8+1.2) X4.5=2X 4.5=9。