题目内容

神机妙算(写出简算过程)
2005×
2003
2004

1
5
+
2
7
)×5×7

999
8
9
+99
8
9
+9
8
9
+
1
3
(1)2005×
2003
2004

=(2004+1)×
2003
2004

=2004×
2003
2004
+1×
2003
2004

=2003+
2003
2004

=2003
2003
2004


(2)(
1
5
+
2
7
)×5×7,
=
1
5
×5×7+
2
7
×5×7,
=7+10,
=17;

(3)999
8
9
+99
8
9
+9
8
9
+
1
3

=(999+99+9)+
8
9
×3+
1
3

=[(1000-1)+(100-1)+(10-1)]+(
8
3
+
1
3
),
=1110-3+3,
=1110.
练习册系列答案
相关题目

违法和不良信息举报电话:027-86699610 举报邮箱:58377363@163.com

精英家教网