题目内容
怎样简便就怎样算.
|
36×(
|
|
| ||||||||||||||||||||||
4-
|
(15-14×
|
|
(6-
|
分析:(1)、(6)、(8)依据四则运算计算方法,先算第二级运算,再算第一级运算,如果只含有同一级运算,按照从左到右顺序计算,有括号先算括号里面的,
(2)、(3)、(4)、(7)运用乘法分配律解答,
(5)依据减法性质解答.
(2)、(3)、(4)、(7)运用乘法分配律解答,
(5)依据减法性质解答.
解答:解:(1)
×
÷
,
=
÷
,
=
;
(2)36×(
+
-
),
=36×
+36×
-36×
,
=24+6-27,
=3;
(3)
×58+42÷8,
=(58+42)×
,
=100×
,
=12.5;
(4)
÷
-
÷
,
=(
-
)×
,
=
×
,
=
;
(5)4-
-
,
=4-(
+
),
=4-1,
=3;
(6)(15-14×
)×
,
=(15-8)×
,
=7×
,
=2
;
(7)
×
+
÷15,
=(
+
)×
,
=1×
,
=
;
(8)(6-
×32)+
,
=(6-4)+
,
=2+
,
=2.75.
| 4 |
| 9 |
| 1 |
| 5 |
| 4 |
| 5 |
=
| 4 |
| 45 |
| 4 |
| 5 |
=
| 1 |
| 9 |
(2)36×(
| 2 |
| 3 |
| 1 |
| 6 |
| 3 |
| 4 |
=36×
| 2 |
| 3 |
| 1 |
| 6 |
| 3 |
| 4 |
=24+6-27,
=3;
(3)
| 1 |
| 8 |
=(58+42)×
| 1 |
| 8 |
=100×
| 1 |
| 8 |
=12.5;
(4)
| 4 |
| 5 |
| 5 |
| 8 |
| 1 |
| 2 |
| 5 |
| 8 |
=(
| 4 |
| 5 |
| 1 |
| 2 |
| 8 |
| 5 |
=
| 3 |
| 10 |
| 8 |
| 5 |
=
| 12 |
| 25 |
(5)4-
| 5 |
| 11 |
| 6 |
| 11 |
=4-(
| 5 |
| 11 |
| 6 |
| 11 |
=4-1,
=3;
(6)(15-14×
| 4 |
| 7 |
| 8 |
| 21 |
=(15-8)×
| 8 |
| 21 |
=7×
| 8 |
| 21 |
=2
| 2 |
| 3 |
(7)
| 3 |
| 7 |
| 1 |
| 15 |
| 4 |
| 7 |
=(
| 3 |
| 7 |
| 4 |
| 7 |
| 1 |
| 15 |
=1×
| 1 |
| 15 |
=
| 1 |
| 15 |
(8)(6-
| 1 |
| 8 |
| 3 |
| 4 |
=(6-4)+
| 3 |
| 4 |
=2+
| 3 |
| 4 |
=2.75.
点评:本题主要考查四则混合运算的运算顺序以及利用运算定律进行简算的能力.
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