题目内容
| 计算下面各题(能简算的要简算) 64×0.125×0.25 |
27×25%+13÷4 |
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考点:小数四则混合运算,运算定律与简便运算,分数的四则混合运算
专题:运算顺序及法则,运算定律及简算
分析:(1)根据数字特点,把64看作8×4×2,运用乘法交换律和结合律简算;
(2)先把除以4换算为乘法,然后根据乘法分配律进行简算即可;
(3)可以先加
,再减去
,然后再根据减法的性质进行简算;
(4)先算小括号内面的,然后根据运算顺序计算;
(5)按照分数四则运算顺序来做,先算小括号内的,然后算中括号内的,最后算中括号外面的.
(2)先把除以4换算为乘法,然后根据乘法分配律进行简算即可;
(3)可以先加
| 1 |
| 6 |
| 2 |
| 7 |
(4)先算小括号内面的,然后根据运算顺序计算;
(5)按照分数四则运算顺序来做,先算小括号内的,然后算中括号内的,最后算中括号外面的.
解答:
解:(1)64×0.125×0.25
=8×4×2×0.125×0.25
=8×0.125×(0.25×4)×2
=1×1×2
=2;
(2)27×25%+13÷4
=27×
+13×
=(27+13)×
=10;
(3)
-
+
-
=
+
)-(
+
)
=1-
=
;
(4)
-(
+
)÷
=
-
×
=
-
=
-
=
;
(5)
×[(
+
)÷
]
=
×[
×
]
=
×
=
.
=8×4×2×0.125×0.25
=8×0.125×(0.25×4)×2
=1×1×2
=2;
(2)27×25%+13÷4
=27×
| 1 |
| 4 |
| 1 |
| 4 |
=(27+13)×
| 1 |
| 4 |
=10;
(3)
| 5 |
| 6 |
| 2 |
| 7 |
| 1 |
| 6 |
| 3 |
| 7 |
=
| 5 |
| 6 |
| 1 |
| 6 |
| 2 |
| 7 |
| 3 |
| 7 |
=1-
| 5 |
| 7 |
=
| 2 |
| 7 |
(4)
| 7 |
| 10 |
| 4 |
| 5 |
| 1 |
| 4 |
| 7 |
| 3 |
=
| 7 |
| 10 |
| 21 |
| 20 |
| 3 |
| 7 |
=
| 7 |
| 10 |
| 9 |
| 60 |
=
| 42 |
| 60 |
| 9 |
| 60 |
=
| 11 |
| 20 |
(5)
| 5 |
| 7 |
| 2 |
| 5 |
| 1 |
| 3 |
| 11 |
| 12 |
=
| 5 |
| 7 |
| 11 |
| 15 |
| 12 |
| 11 |
=
| 5 |
| 7 |
| 4 |
| 5 |
=
| 4 |
| 7 |
点评:完成本题要注意分析式中数据,运用合适的简便方法计算.
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