题目内容
计算:
|
|
2.6-1
|
0.5-
|
分析:(1)运用加法交换律和加法结合律解答,
(2)依据减法性质解答,
(3)(4)按照从左到右顺序解答.
(2)依据减法性质解答,
(3)(4)按照从左到右顺序解答.
解答:解:(1)
+
-
+
,
=(
-
)+(
+
),
=
+1,
=1
;
(2)
-(
+
),
=
-
-
,
=
-
,
=0;
(3)2.6-1
+
,
=1.4+
,
=2.15;
(4)0.5-
+
,
=
+
,
=
.
| 7 |
| 8 |
| 1 |
| 4 |
| 1 |
| 8 |
| 3 |
| 4 |
=(
| 7 |
| 8 |
| 1 |
| 8 |
| 1 |
| 4 |
| 3 |
| 4 |
=
| 3 |
| 4 |
=1
| 3 |
| 4 |
(2)
| 7 |
| 9 |
| 1 |
| 3 |
| 4 |
| 9 |
=
| 7 |
| 9 |
| 4 |
| 9 |
| 1 |
| 3 |
=
| 1 |
| 3 |
| 1 |
| 3 |
=0;
(3)2.6-1
| 1 |
| 5 |
| 3 |
| 4 |
=1.4+
| 3 |
| 4 |
=2.15;
(4)0.5-
| 1 |
| 3 |
| 1 |
| 8 |
=
| 1 |
| 6 |
| 1 |
| 8 |
=
| 7 |
| 24 |
点评:明确四则运算计算方法,以及正确运用简便算法是解答本题的关键.
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