问题 解答题
计算题.
(1)37.5%×40+
3
8
×40
(2)
2
5
×22%+0.78×40%
(3)
12
25
÷17+
13
25
×
1
17
(4)4.5÷[(10-2.5)×2].
答案

(1)37.5%×40+

3
8
×40,

=(37.5%+

3
8
)×40,

=0.75×40,

=30;

(2)

2
5
×22%+0.78×40%,

=0.4×22%+0.78×0.4,

=0.4×(22%+0.78),

=0.4×1,

=0.4;

(3)

12
25
÷17+
13
25
×
1
17

=

12
25
×
1
17
+
13
25
×
1
17

=(

12
25
+
13
25
)×
1
17

=1×

1
17

=

1
17

(4)4.5÷[(10-2.5)×2],

=4.5÷[7.5×2],

=4.5÷15,

=0.3.

单项选择题
单项选择题