问题 解答题
计算下面各题,最后两个小题要用简便方法计算.
1
4
÷〔
5
8
×(
1
6
+
1
3
)〕
6
7
÷18+
2
3
4
7
-
3
14
)÷
1
28
2.5×32×12.5.
答案

(1)

1
4
÷〔
5
8
×(
1
6
+
1
3
)〕,

=

1
4
÷〔
5
8
×
1
2
〕,

=

1
4
÷
5
16

=

4
5

(2)

6
7
÷18+
2
3

=

1
21
+
2
3

=

5
7

(3)(

4
7
-
3
14
)÷
1
28

=(

4
7
-
3
14
)×28,

=

4
7
×28-
3
14
×28,

=10;

(4)2.5×32×12.5,

=2.5×(4×8)×12.5,

=(2.5×4)×(8×12.5),

=10×100,

=1000.

填空题
问答题 简答题