题目内容
怎样算简便就怎样算.
|
[
| ||||||||||
2010÷
|
1.25×17.6+36.1÷80%+2.63×12.5. |
分析:(1)先同时算出乘法和除法,再算加法,
(2)先算小括号里的加法,再算在括号里的除法,再算在括号里的减法,最后算括号外的乘法,
(3)把除以
化成乘以
,再把2010化成(2009+1),运用乘法的分配律进行简算即可,
(4)把除以80%化成乘以
,再运用乘法的分配律进行简算.
(2)先算小括号里的加法,再算在括号里的除法,再算在括号里的减法,最后算括号外的乘法,
(3)把除以
2009 |
2008 |
2008 |
2009 |
(4)把除以80%化成乘以
5 |
4 |
解答:解:(1)
×58+42÷8,
=
+
,
=
;
(2)[
-0÷(
+
)]×
,
=[
-0÷
]×
,
=[
-0]×
,
=
×
,
=
;
(3)2010÷
,
=(2009+1)×
,
=2009×
+1×
,
=2008+
,
=2008
;
(4)1.25×17.6+36.1÷80%+2.63×12.5,
=1.25×17.6+36.1×
+26.3×1.25,
=1.25×(17.6+36.1+26.3),
=1.25×80,
=100.
1 |
8 |
=
29 |
4 |
21 |
4 |
=
25 |
2 |
(2)[
4 |
5 |
1 |
3 |
2 |
5 |
5 |
8 |
=[
4 |
5 |
11 |
15 |
5 |
8 |
=[
4 |
5 |
5 |
8 |
=
4 |
5 |
5 |
8 |
=
1 |
2 |
(3)2010÷
2009 |
2008 |
=(2009+1)×
2008 |
2009 |
=2009×
2008 |
2009 |
2008 |
2009 |
=2008+
2008 |
2009 |
=2008
2008 |
2009 |
(4)1.25×17.6+36.1÷80%+2.63×12.5,
=1.25×17.6+36.1×
5 |
4 |
=1.25×(17.6+36.1+26.3),
=1.25×80,
=100.
点评:考查了分数、小数四则混合运算的顺序,灵活运用运算定律进行简算.
练习册系列答案
相关题目