题目内容
用递等式计算,能简算的要简算.
|
60.62-(9.2+12.62) | ||||||||||||||
6.8+
|
| ||||||||||||||
|
|
分析:(1)按照从左到右顺序即可解答;
(2)(4)运用减法性质即可解答;
(3)(5)运用加法交换律和结合律即可解答;
(6)先运用减法性质,再运用加法交换律即可解答.
(2)(4)运用减法性质即可解答;
(3)(5)运用加法交换律和结合律即可解答;
(6)先运用减法性质,再运用加法交换律即可解答.
解答:解:(1)
+
+
,
=
+
,
=1
;
(2)60.62-(9.2+12.62),
=60.62-9.2-12.62,
=48-9.2,
=38.8;
(3)6.8+
+3.2+
,
=(6.8+3.2)+(
+
),
=10+1,
=11;
(4)
-
-
,
=
-(
+
),
=
-1,
=
;
(5)
+
+
-
,
=(
+
)+(
-
),
=1+
,
=1
;
(6)
-(
-
),
=
+
-
,
=1-
,
=
.
| 4 |
| 5 |
| 11 |
| 15 |
| 3 |
| 10 |
=
| 23 |
| 15 |
| 3 |
| 10 |
=1
| 5 |
| 6 |
(2)60.62-(9.2+12.62),
=60.62-9.2-12.62,
=48-9.2,
=38.8;
(3)6.8+
| 1 |
| 6 |
| 5 |
| 6 |
=(6.8+3.2)+(
| 1 |
| 6 |
| 5 |
| 6 |
=10+1,
=11;
(4)
| 15 |
| 11 |
| 3 |
| 7 |
| 4 |
| 7 |
=
| 15 |
| 11 |
| 3 |
| 7 |
| 4 |
| 7 |
=
| 15 |
| 11 |
=
| 4 |
| 11 |
(5)
| 9 |
| 11 |
| 5 |
| 6 |
| 2 |
| 11 |
| 1 |
| 6 |
=(
| 9 |
| 11 |
| 2 |
| 11 |
| 5 |
| 6 |
| 1 |
| 6 |
=1+
| 2 |
| 3 |
=1
| 2 |
| 3 |
(6)
| 7 |
| 8 |
| 7 |
| 10 |
| 1 |
| 8 |
=
| 7 |
| 8 |
| 1 |
| 8 |
| 7 |
| 10 |
=1-
| 7 |
| 10 |
=
| 3 |
| 10 |
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.
练习册系列答案
相关题目