题目内容
(1)
|
(2)12×(
| ||||||||||||
(3)解方程:(
|
(4)解方程:
|
分析:(1)按照从左向右的顺序进行计算;
(2)根据乘法分配律进行简算;
(3)先算
-
=
,然后等式的两边同时除以
;
(4)等式的两边同时乘
,然后等式的两边同时除以
.
(2)根据乘法分配律进行简算;
(3)先算
| 1 |
| 2 |
| 1 |
| 4 |
| 1 |
| 4 |
| 1 |
| 4 |
(4)等式的两边同时乘
| 1 |
| 6 |
| 2 |
| 3 |
解答:解:(1)
÷2×
÷3×
=
×
÷3×
=
÷3×
=
×
=
;
(2)12×(
+
-
)
=12×
+12×
-12×
=6+9-10
=15-10
=5;
(3)(
-
)x=
x=
x÷
=
÷
x=
;
(4)
x÷
=12
x÷
×
=12×
x=2
x÷
=2÷
x=3.
| 1 |
| 4 |
| 1 |
| 2 |
| 1 |
| 3 |
=
| 1 |
| 8 |
| 1 |
| 2 |
| 1 |
| 3 |
=
| 1 |
| 16 |
| 1 |
| 3 |
=
| 1 |
| 48 |
| 1 |
| 3 |
=
| 1 |
| 144 |
(2)12×(
| 1 |
| 2 |
| 3 |
| 4 |
| 5 |
| 6 |
=12×
| 1 |
| 2 |
| 3 |
| 4 |
| 5 |
| 6 |
=6+9-10
=15-10
=5;
(3)(
| 1 |
| 2 |
| 1 |
| 4 |
| 1 |
| 3 |
| 1 |
| 4 |
| 1 |
| 3 |
| 1 |
| 4 |
| 1 |
| 4 |
| 1 |
| 3 |
| 1 |
| 4 |
x=
| 4 |
| 3 |
(4)
| 2 |
| 3 |
| 1 |
| 6 |
| 2 |
| 3 |
| 1 |
| 6 |
| 1 |
| 6 |
| 1 |
| 6 |
| 2 |
| 3 |
| 2 |
| 3 |
| 2 |
| 3 |
| 2 |
| 3 |
x=3.
点评:考查了运算定律与简便运算,四则混合运算.注意运算顺序和运算法则,灵活运用所学的运算定律简便计算.
练习册系列答案
相关题目