题目内容
|
|
9.625-
|
2
|
分析:(1)利用加法交换律简算;
(2)利用加法交换律与减法的性质简算;
(3)(4)利用减法的性质简算.
(2)利用加法交换律与减法的性质简算;
(3)(4)利用减法的性质简算.
解答:解:(1)
+
-
=
-
+
=1+
=1
;
(2)
-
+
-
=
+
-(
+
)
=1-1
=0;
(3)9.625-
-
=9.625-(
+
)
=9.625-2
=7.625;
(4)2
-(
+
)
=2
-
-
=2-
=1
.
11 |
9 |
5 |
8 |
2 |
9 |
=
11 |
9 |
2 |
9 |
5 |
8 |
=1+
5 |
8 |
=1
5 |
8 |
(2)
1 |
2 |
11 |
15 |
1 |
2 |
4 |
15 |
=
1 |
2 |
1 |
2 |
4 |
15 |
11 |
15 |
=1-1
=0;
(3)9.625-
16 |
9 |
2 |
9 |
=9.625-(
16 |
9 |
2 |
9 |
=9.625-2
=7.625;
(4)2
2 |
9 |
2 |
9 |
5 |
12 |
=2
2 |
9 |
2 |
9 |
5 |
12 |
=2-
5 |
12 |
=1
7 |
12 |
点评:分数加减混合运算,注意数字特点,灵活选用适当的方法和运算定律简算.
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