题目内容
用自己喜欢的方法计算下面各题.
+
-
-
+
+
+
+
0.125+
-
+
.
| 8 |
| 15 |
| 4 |
| 9 |
| 2 |
| 15 |
| 1 |
| 12 |
| 1 |
| 4 |
| 5 |
| 12 |
| 9 |
| 7 |
| 1 |
| 8 |
| 3 |
| 8 |
| 5 |
| 7 |
0.125+
| 7 |
| 11 |
| 7 |
| 11 |
| 71 |
| 8 |
分析:(1)根据加法交换律进行计算;
(2)根据加法交换律进行计算
(3)根据加法交换律和结合律进行计算;
(4)根据加法交换律和结合律进行计算.
(2)根据加法交换律进行计算
(3)根据加法交换律和结合律进行计算;
(4)根据加法交换律和结合律进行计算.
解答:解:
(1)
+
-
,
=
-
+
,
=
+
,
=
;
(2)
-
+
,
=
+
-
,
=
-
,
=
;
(3)
+
+
+
,
=(
+
)+(
+
),
=2+
,
=2
;
(4)0.125+
-
+
,
=(0.125+
)+(
-
),
=9+0,
=9.
(1)
| 8 |
| 15 |
| 4 |
| 9 |
| 2 |
| 15 |
=
| 8 |
| 15 |
| 2 |
| 15 |
| 4 |
| 9 |
=
| 2 |
| 5 |
| 4 |
| 9 |
=
| 38 |
| 45 |
(2)
| 1 |
| 12 |
| 1 |
| 4 |
| 5 |
| 12 |
=
| 1 |
| 12 |
| 5 |
| 12 |
| 1 |
| 4 |
=
| 1 |
| 2 |
| 1 |
| 4 |
=
| 1 |
| 4 |
(3)
| 9 |
| 7 |
| 1 |
| 8 |
| 3 |
| 8 |
| 5 |
| 7 |
=(
| 9 |
| 7 |
| 5 |
| 7 |
| 1 |
| 8 |
| 3 |
| 8 |
=2+
| 1 |
| 2 |
=2
| 1 |
| 2 |
(4)0.125+
| 7 |
| 11 |
| 7 |
| 11 |
| 71 |
| 8 |
=(0.125+
| 71 |
| 8 |
| 7 |
| 11 |
| 7 |
| 11 |
=9+0,
=9.
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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