六上数学,用乘法分配律解分数乘法简便计算

六上数学,用乘法分配律解分数乘法简便计算


简介:
①7×8×(+) =7×8×+7×8× =8+7 =15 ②2001× =(2000+1)× =2000×+1× =1999+ =1999 ③×(72-4.8) =×72-×4.8 =45-3 =42 ④48×(+ - ) =48×+48×-48× =12+40-42 =10 ⑤2.4×(+-) =2.4×+2.4×-2.4× =1.8+0.4-1 =2.2-1 =1.2 ⑥(-)×60 =×60-×60 =50-48