题目内容
(2007?万安县)下列各题怎样算简便就怎样算.
+
×
÷2
[1-(
+
)]÷25%
×0.75+
×
(
+
-
)×24.
1 |
6 |
3 |
4 |
2 |
3 |
[1-(
1 |
4 |
3 |
8 |
17 |
24 |
17 |
24 |
1 |
4 |
(
3 |
4 |
1 |
2 |
7 |
12 |
分析:
+
×
÷2,把除以2改为乘
,注意分数之间分子与分母的约分;
[1-(
+
)]÷25%,先算小括号内的,再算中括号内的,最后算括号外的;
×0.75+
×
,把0.75化成分数,或把
化成小数,用乘法分配律的逆运算简算;
(
+
-
)×24,用乘法分配律简算.
1 |
6 |
3 |
4 |
2 |
3 |
1 |
2 |
[1-(
1 |
4 |
3 |
8 |
17 |
24 |
17 |
24 |
1 |
4 |
1 |
4 |
(
3 |
4 |
1 |
2 |
7 |
12 |
解答:解:
+
×
÷2,
=
+
×
×
,
=
+
,
=
+
,
=
;
[1-(
+
)]÷25%,
=[1-
]÷
,
=
×4,
=1
;
×0.75+
×
,
=
×
+
×
,
=(
+
)×
,
=1×
,
=
;
(
+
-
)×24,
=
×24+
×24-
×24,
=18+12-14,
=16.
1 |
6 |
3 |
4 |
2 |
3 |
=
1 |
6 |
3 |
4 |
2 |
3 |
1 |
2 |
=
1 |
6 |
1 |
4 |
=
2 |
12 |
3 |
12 |
=
5 |
12 |
[1-(
1 |
4 |
3 |
8 |
=[1-
5 |
8 |
1 |
4 |
=
3 |
8 |
=1
1 |
2 |
17 |
24 |
17 |
24 |
1 |
4 |
=
17 |
24 |
3 |
4 |
17 |
24 |
1 |
4 |
=(
3 |
4 |
1 |
4 |
17 |
24 |
=1×
17 |
24 |
=
17 |
24 |
(
3 |
4 |
1 |
2 |
7 |
12 |
=
3 |
4 |
1 |
2 |
7 |
12 |
=18+12-14,
=16.
点评:此题考查了学生对运算顺序的掌握情况,以及运用所学知识灵活巧算的能力.
练习册系列答案
相关题目