五年级上册数学小数乘法简便运算专项练习

五年级上册数学小数乘法简便运算专项练习乘法交换律0.25×8.5×412.5×0.96×0.80.5×0.34×0.6=0.25×4×8.5=12.5×0.8×0.96=0.5×0.6×0.34=1×8.5=10×0.96=0.3×0.34=8.5=9.6=0.102乘法结合律4.36×12.5×80.95×0.25×40.75×50×0.4=4.36×(12.5×8)=0.95×(0.25×4)=0.75×(50×0.4)=4.36×100=0.95×1=0.75×20=436=0.95=15拆数+乘法结合律0.125×8.80.25×0.280.125×3.2×2.5=0.125×8×1.1=0.25×4×0.07=(0.125×8)×(0.4×2.5)=1×1.1=1×0.07=1×1=1.1=0.07=1四、乘法分配律(1.25-0.125)×8(125+2.5)×0.83.72×3.5+6.28×3.5=1.25×8-0.125×8=125×0.8+2.5×0.8=3.5×(3.5+6.28)=10-1=1+1=3.5×10=9(正用)=2(正用)=35(逆用)