题目内容
能简算的要简算
|
|
|
|
分析:(1)
+
+
+
,运用加法交换律和结合律进行简算;
(2)
×(
+
),根据分数四则混合运算的顺序,按照分数四则运算的计算法则进行计算;
(3)
÷(3-
-
),根据减法的运算性质进行简算;
(4)
÷[
-(
+
)],根据分数四则混合运算的顺序,按照分数四则运算的计算法则进行计算.
| 5 |
| 7 |
| 5 |
| 6 |
| 2 |
| 7 |
| 1 |
| 6 |
(2)
| 1 |
| 15 |
| 1 |
| 3 |
| 1 |
| 12 |
(3)
| 1 |
| 4 |
| 5 |
| 13 |
| 8 |
| 13 |
(4)
| 4 |
| 9 |
| 5 |
| 6 |
| 1 |
| 6 |
| 1 |
| 3 |
解答:解:(1)
+
+
+
,
=(
+
)+(
+
),
=1+1,
=2;
(2)
×(
+
),
=
×
,
=
;
(3)
÷(3-
-
),
=
÷[3-(
+
)],
=
÷[3-1],
=
÷2,
=
×
,
=
;
(4)
÷[
-(
+
)],
=
÷[
-
],
=
÷
,
=
×
,
=
,
=1
.
| 5 |
| 7 |
| 5 |
| 6 |
| 2 |
| 7 |
| 1 |
| 6 |
=(
| 5 |
| 7 |
| 2 |
| 7 |
| 5 |
| 6 |
| 1 |
| 6 |
=1+1,
=2;
(2)
| 1 |
| 15 |
| 1 |
| 3 |
| 1 |
| 12 |
=
| 1 |
| 15 |
| 5 |
| 12 |
=
| 1 |
| 36 |
(3)
| 1 |
| 4 |
| 5 |
| 13 |
| 8 |
| 13 |
=
| 1 |
| 4 |
| 5 |
| 13 |
| 8 |
| 13 |
=
| 1 |
| 4 |
=
| 1 |
| 4 |
=
| 1 |
| 4 |
| 1 |
| 2 |
=
| 1 |
| 8 |
(4)
| 4 |
| 9 |
| 5 |
| 6 |
| 1 |
| 6 |
| 1 |
| 3 |
=
| 4 |
| 9 |
| 5 |
| 6 |
| 3 |
| 6 |
=
| 4 |
| 9 |
| 2 |
| 6 |
=
| 4 |
| 9 |
| 6 |
| 2 |
=
| 4 |
| 3 |
=1
| 1 |
| 3 |
点评:此题考查的目的是掌握分数四则混合运算的顺序、分数四则运算的计算法则,并且能够灵活选择简便方法进行计算.
练习册系列答案
相关题目