问题 解答题
计算下面各题.
9.8-1.8×0.45
5
7
+
2
7
÷
2
21
5
6
-
1
8
)÷
5
12
8
9
÷
4
15
-
5
9
)×
6
25
答案

(1)9.8-1.8×0.45,

=9.8-0.81,

=8.99;

(2)

5
7
+
2
7
÷
2
21

=

5
7
+3,

=3

5
7

(3)(

5
6
-
1
8
)÷
5
12

=

17
24
÷
5
12

=

17
10

(4)(

8
9
÷
4
15
-
5
9
)×
6
25

=(

10
3
-
5
9
)×
6
25

=

25
9
×
6
25

=

2
3

单项选择题
单项选择题