问题 解答题
用递等式计算
①(
2
3
-
2
5
)÷(
1
8
+
5
12

②(
4
5
+
1
4
)÷
7
3
+
7
10

③253+292÷73.
答案

①(

2
3
-
2
5
)÷(
1
8
+
5
12
),

=(

10
15
-
6
15
)÷(
3
24
+
10
24
),

=

4
15
÷
13
24

=

4
15
×
24
13

=

32
65

②(

4
5
+
1
4
)÷
7
3
+
7
10

=(

16
20
+
5
20
)÷
7
3
+
7
10

=

21
20
×
3
7
+
7
10

=

9
20
+
14
20

=1

3
20

③253+292÷73,

=253+4,

=257.

单项选择题 A1/A2型题
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