题目内容
怎样算简便就怎样算.
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|
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45×(
|
7÷
|
|
分析:(1)运用乘法分配律计算;
(2)先算乘法,再算加法;
(3)先算除法,按照从一个数里连续减去两个数等于从这个数里减去这两个数的和;
(4)运用乘法分配律计算;
(5)按照运算顺序计算即可;
(6)按照运算顺序计算即可.
(2)先算乘法,再算加法;
(3)先算除法,按照从一个数里连续减去两个数等于从这个数里减去这两个数的和;
(4)运用乘法分配律计算;
(5)按照运算顺序计算即可;
(6)按照运算顺序计算即可.
解答:解:(1)
×
+
×
,
=(
+
)×
,
=1×
,
=
;
(2)
+
×
,
=
+
,
=
+
,
=
;
(3)
-
÷
-
,
=
-
-
,
=
-(
+
),
=
-1,
=
;
(4)45×(
+
),
=45×
+45×
,
=9+15,
=24;
(5)7÷
-
÷7,
=7×
-
×
,
=9-
,
=8
;
(6)
÷[
×(
-
)],
=
÷[
×
],
=
×4,
=
.
| 1 |
| 8 |
| 7 |
| 11 |
| 4 |
| 11 |
| 1 |
| 8 |
=(
| 7 |
| 11 |
| 4 |
| 11 |
| 1 |
| 8 |
=1×
| 1 |
| 8 |
=
| 1 |
| 8 |
(2)
| 2 |
| 3 |
| 7 |
| 6 |
| 3 |
| 14 |
=
| 2 |
| 3 |
| 1 |
| 4 |
=
| 8 |
| 12 |
| 3 |
| 12 |
=
| 11 |
| 12 |
(3)
| 18 |
| 7 |
| 1 |
| 2 |
| 3 |
| 4 |
| 1 |
| 3 |
=
| 18 |
| 7 |
| 2 |
| 3 |
| 1 |
| 3 |
=
| 18 |
| 7 |
| 2 |
| 3 |
| 1 |
| 3 |
=
| 18 |
| 7 |
=
| 11 |
| 7 |
(4)45×(
| 1 |
| 5 |
| 1 |
| 3 |
=45×
| 1 |
| 5 |
| 1 |
| 3 |
=9+15,
=24;
(5)7÷
| 7 |
| 9 |
| 7 |
| 9 |
=7×
| 9 |
| 7 |
| 7 |
| 9 |
| 1 |
| 7 |
=9-
| 1 |
| 9 |
=8
| 8 |
| 9 |
(6)
| 2 |
| 3 |
| 9 |
| 14 |
| 5 |
| 6 |
| 4 |
| 9 |
=
| 2 |
| 3 |
| 9 |
| 14 |
| 7 |
| 18 |
=
| 2 |
| 3 |
=
| 8 |
| 3 |
点评:解决本题要仔细分析数据,选取适合的方法解答.
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