问题 解答题
计算下面各题.
2.7-0.8+1.3-0.19
3.5×0.8+6.5×80%
2
15
÷[1-(
1
5
+
1
3
)]

15
1
3
+2
5
11
-5
1
3
答案

(1)2.7-0.8+1.3-0.19,

=(2.7+1.3)-(0.8+0.19),

=4-0.99,

=3.01;

(2)3.5×0.8+6.5×80%,

=3.5×0.8+6.5×0.8,

=(3.5+6.5)×0.8,

=10×0.8,

=8;

(3)

2
15
÷[1-(
1
5
+
1
3
)],

=

2
15
÷[1-
8
15
],

=

2
15
÷
7
15

=

2
7

(4)15

1
3
+2
5
11
-5
1
3

=15

1
3
-5
1
3
+2
5
11

=10+2

5
11

=12

5
11

单项选择题
单项选择题