(2007-1)+(2006-2)+(2005-3)+……+(1005-1003)

分类: 作业答案 • 2021-12-31 10:22:41

问题描述：

答

(2007-1)+(2006-2)+(2005-3)+……+(1005-1003)
=(2007-1003)+(2006-10022)+(2005-1001)+……+(1005-1)
=1004×1003
=1007012