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时间:2017-11-13
《小学数学五年级上册简便计算练习(答案卷)》由会员上传分享,免费在线阅读,更多相关内容在教育资源-天天文库。
1、小学数学五年级上册简便计算练习(答案卷)一、归类练习:(带★题稍难,其他题都是基础题,必须掌握。)3.29+0.73+2.27 3.29-0.73-2.27 7.5+2.5-7.5+2.5=3.29+(0.73+2.27) =3.29-(0.73+2.27) =(7.5-7.5)+(2.5+2.5)=3.29+3 =3.29-3 =0+5=6.29=0.29=5(加法结合律)(减法的性质)(同级运算交换)7.325-3.29-3.325 7.325-(5.325+1.7) 7
2、.325-(5.325-1.7)=7.325-3.325-3.29 =7.325-5.325-1.7 =7.325-5.325+1.7=4-3.29 =2-1.7 =2+1.7=0.71=0.3=3.7(减法交换)(减法的性质)(前面减号,脱括号变符号)3.29+0.73-2.29+2.27 3.29×0.25×4 0.125×8.8 =(3.29-2.29)+(0.73+2.27) =3.29×(0.25×4) =0.125×8×1.1=1+3 =3.29×1
3、 =1×1.1=4=3.29=1.1(同级运算交换)(乘法结合律)(先拆数,乘法结合律) 0.25×0.28 0.125×3.2×2.5 35×10.2=0.25×4×0.07 =(0.125×8)×(0.4×2.5) =35×(10+0.2)=1×0.07 =1×1 =35×10+35×0.2=0.07=1=350+7(先拆数,乘法结合律)(拆数,乘法结合律)=357(拆数,乘法分配律) 0.25×4÷0.25×4 3.5×9.9
4、 3.5×99+3.5=(0.25÷0.25)×(4×4) =3.5×(10-0.1) =3.5×(99+1)=1×16=3.5×10-3.5×0.1=3.5×100=16=35-0.35=350(同级运算交换)=34.65(乘法分配律)(拆数,乘法分配律)3.5×101-3.5 3.5×9.9+3.5×0.1 ★3.5×2.7+35×0.73=3.5×(101-1) =3.5×(9.9+0.1) =3.5×2.7+3.5×7.3=3.5×100=3.5
5、×10=3.5×(2.7+7.3)=350=35=3.5×10(乘法分配律)(乘法分配律)=35(先利用积不变的规律转化,然后再用乘法分配律)3.5×2.7-3.5×0.7 ★(32+5.6)÷0.8 ★3.5÷0.6-0.5÷0.6=3.5×(2.7-0.7) =32÷0.8+5.6÷0.8 =(3.5-0.5)÷0.6=3.5×2=40+7=3÷0.6=7=47=5(乘法分配律)(后2题类似分配律,但只适用于(a+b)÷c和(a-b)÷c,而a÷(b+c)和a÷(b-c)不能用。)4.9÷1.4
6、7÷0.25÷4 ★ 7÷0.125 =4.9÷(7×0.2) =7÷(0.25×4) =7×8=4.9÷7÷0.2=7÷1=56=0.7÷0.2=7(乘除法转化规律,转化时=3.5符号相反,转化前后的2数(拆数,除法的性质)(除法的性质)相乘得1。)7.35÷(7.35×0.25) ★7.35÷(7.35÷0.25) =7.35÷7.35÷0.25 =7.35÷7.35×0.25=1÷0.25=1×0.25=4=0.25(除法的性质)(前面是除号,脱括号符号相反)二、混合练习: 3.07-0.3
7、8-1.62 1.29+3.7+2.71+6.3 8-2.45-1.55=3.07-(0.38+1.62) =(1.29+2.71)+(3.7+6.3) =8-(2.45+1.55)=3.07-2=4+10=8-4=1.07=14=4(减法的性质)(加法交换律和加法结合律)(减法的性质)3.25+1.79-0.59+1.75 23.4-0.8-13.4-7.2 0.32×403=(3.25+1.75)+(1.79-0.59) =(23.4-13.4)-0.8-7.2 =0.32×(400+3)=5+1.2
8、=10-(0.8+7.2
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