问题 解答题
怎样简便就怎样算.
9
11
×
7
15
×
11
3

5
7
×
6
13
+
7
13
×
5
7

13
88
×87+
13
88

(
1
3
+
2
5
)×3×5
答案

(1)

9
11
×
7
15
×
11
3
=
7
5

(2)

5
7
×
6
13
+
7
13
×
5
7

=(

6
13
+
7
13
)×
5
7

=1×

5
7

=

5
7

(3)

13
88
×87+
13
88

=

13
88
×(87+1),

=

13
88
×88,

=13;

(4)(

1
3
+
2
5
)×3×5,

=

1
3
×3×5+
2
5
×3×5,

=5+6,

=11.

单项选择题
单项选择题