题目内容
脱式计算,能简算的要简算.
+
-
1-(
+
)
-(
-
)
+
+
-
.
| 2 |
| 3 |
| 4 |
| 5 |
| 2 |
| 3 |
1-(
| 1 |
| 4 |
| 3 |
| 8 |
| 6 |
| 7 |
| 11 |
| 14 |
| 1 |
| 2 |
| 5 |
| 9 |
| 6 |
| 11 |
| 4 |
| 9 |
| 4 |
| 11 |
考点:分数的加法和减法
专题:运算顺序及法则
分析:①把
+
-
变成
-
+
计算
②先算括号里的加法,再算括号外的减法
③先算括号里的减法,再算括号外的减法
④把
+
+
-
变成
+
+
-
计算
| 2 |
| 3 |
| 4 |
| 5 |
| 2 |
| 3 |
| 2 |
| 3 |
| 2 |
| 3 |
| 4 |
| 5 |
②先算括号里的加法,再算括号外的减法
③先算括号里的减法,再算括号外的减法
④把
| 5 |
| 9 |
| 6 |
| 11 |
| 4 |
| 9 |
| 4 |
| 11 |
| 5 |
| 9 |
| 4 |
| 9 |
| 6 |
| 11 |
| 4 |
| 11 |
解答:
解:①
+
-
=
-
+
=
②1-(
+
)
=1-(
+
)
=1-
=
③
-(
-
)
=
-(
-
)
=
-
=
-
=
④
+
+
-
=(
+
)+(
-
)
=1+
=1
| 2 |
| 3 |
| 4 |
| 5 |
| 2 |
| 3 |
=
| 2 |
| 3 |
| 2 |
| 3 |
| 4 |
| 5 |
=
| 4 |
| 5 |
②1-(
| 1 |
| 4 |
| 3 |
| 8 |
=1-(
| 2 |
| 8 |
| 3 |
| 8 |
=1-
| 5 |
| 8 |
=
| 3 |
| 8 |
③
| 6 |
| 7 |
| 11 |
| 14 |
| 1 |
| 2 |
=
| 6 |
| 7 |
| 11 |
| 14 |
| 7 |
| 14 |
=
| 6 |
| 7 |
| 4 |
| 14 |
=
| 6 |
| 7 |
| 2 |
| 7 |
=
| 4 |
| 7 |
④
| 5 |
| 9 |
| 6 |
| 11 |
| 4 |
| 9 |
| 4 |
| 11 |
=(
| 5 |
| 9 |
| 4 |
| 9 |
| 6 |
| 11 |
| 4 |
| 11 |
=1+
| 2 |
| 11 |
=1
| 2 |
| 11 |
点评:本题考查分数的四则混合运算,注意应用运算定律及其简便方法.
练习册系列答案
相关题目