问题 解答题
计算下面各题,能简算的简算.
5
12
÷
15
21
+
1
4
×
3
5

②58×102
9
18
×[
3
16
-(
7
16
-
1
4
)]
④0.888×125×73+999×73.
答案

5
12
÷
15
21
+
1
4
×
3
5

=

5
12
×
21
15
+
1
4
×
3
5

=

7
12
+
3
20

=

11
15

②58×102,

=58×(100+2),

=58×100+58×2,

=5800+116,

=5916;

9
18
×[
3
16
-(
7
16
-
1
4
)],

=

9
18
×[
3
16
-
3
16
],

=

9
18
×0.

=0;

④0.888×125×73+999×73,

=[(0.8+0.08+0.008)×125]×73+999×73,

=[0.8×125+0.08×125+0.008×125]×73+999×73,

=[100+10+1]×73+999×73,

=111×73+999×73,

=(111+999)×73,

=1110×73,

=81030.

单项选择题 A1/A2型题
单项选择题