用简便方法计算下面各题.18.5×3034.5-8.9-9.9-10.9(8-0.8)×1253.5×1.02+35×0.098.
(1)18.5×30, =18×30+0.5×30, =540+15, =555; (2)34.5-8.9-9.9-10.9, =34.5-9-10-11+0.3, =34.5-(9+10+11)+0.3, =34.5-30+0.3, =4.5+0.3, =4.8; (3)(8-0.8)×125, =8×125-0.8×125, =1000-100, =900; (4)3.5×1.02+35×0.098, =3.5×1.02+3.5×0.98, =3.5×(1.02+0.98), =3.5×2, =7; |
用简便方法计算下面各题.18.5×3034.5-8.9-9.9-10.9(8-0.8)×1253.5×...
用简便方法计算下面各题.18.5×30 34.5-8.9-9.9-10.9 (8-0.8)×125 3.5×1.02+35×0.098.答案 解析 (1)18.5×30,把18.5拆分为18+0.5,再运用乘法分配律进行简算;(2)34.5-8.9-9.9-10.9,根据减法的运算性质进行简算;(3)(8-0.8)×125,运用乘法分配律进行...
用简便方法计算下面各题.18.5×3034.5-8.9-9.9-10.9(
(1)18.5×30,=18×30+0.5×30,=540+15,=555;(2)34.5-8.9-9.9-10.9,=34.5-9-10-11+0.3,=34.5-(9+10+11)+0.3,=34.5-30+0.3,=4.5+0.3,=4.8;(3)(8-0.8)×125,=8×125-0.8×125,=1000-100,=900;(4)3.5×1.02+35×0.098,=...