问题 解答题
合理、灵活地计算.
0.45×14+86×45%
2
5
+
3
5
÷
9
10
(50%-
2
5
)×20.
答案

(1)0.45×14+86×45%,

=0.45×(14+86),

=0.45×100,

=45;

(2)

2
5
+
3
5
÷
9
10

=

2
5
+
2
3

=

16
15

(3)(50%-

2
5
)×20,

=

1
2
×20-
2
5
×20,

=10-8,

=2.

单项选择题
单项选择题