问题 解答题
用简便方法计算.
5
6
×
5
9
+
5
9
×
1
6
1
10
+
1
4
)×4
5
18
×
1
4
×
9
10
答案

(1)

5
6
×
5
9
+
5
9
×
1
6

=(

5
6
+
1
6
)×
5
9

=1×

5
9

=

5
9

(2)(

1
10
+
1
4
)×4,

=

1
10
×4+
1
4
×4,

=

2
5
+1,

=1

2
5

(3)

5
18
×
1
4
×
9
10

=

5
18
×
9
10
×
1
4

=

1
4
×
1
4

=

1
16

单项选择题
单项选择题