四年级数学上册『运算律』简便计算专项训练

四年级数学上册『运算律』简便计算专项训练


简介:
404×25 =101×(4×25) =101×100 =10100 36×31 =36×(30+1) =36×30+36 =1080+36 =1116 98×26 =(100-2)×26 =100×26-2×26 =2600-52 =2548 125×(8+20) =125×8+125×20 =1000+2500 =3500