问题 解答题
计算下面各题.
①2297-156×720÷390
②4.7×85+47×1.5
4
5
+〔
9
14
×(
5
6
-
4
9
)〕
④3-
3
2
×
10
21
-
2
7
答案

①2297-156×720÷390,

=2297-112320÷390,

=2297-288,

=2009;

②4.7×85+47×1.5,

=4.7×85+4.7×15,

=4.7×(85+15),

=4.7×100,

=470;

4
5
+[
9
14
×(
5
6
-
4
9
)],

=

4
5
+[
9
14
×
7
18
],

=

4
5
+
1
4

=

21
20

④3-

3
2
×
10
21
-
2
7

=3-

5
7
-
2
7

=3-(

5
7
+
2
7
),

=3-1,

=2.

单项选择题
单项选择题