六上数学.分数乘法分配律.简便计算

六上数学.分数乘法分配律.简便计算


简介:
(-)×60 =×60-×60 =35-12 =23 (+)×18 =×18+×18 =3+16 =19 (-)× =×-× =3-2 =1 (+)×5 =×5+×5 =+1 =1 (+)×27 =×27+×27 =24+4 =28 90×(+) =90×+90× =25+21 =46