2-1+4-3+6-5+8-7+……+500-499=?
问题描述:
2-1+4-3+6-5+8-7+……+500-499=?
答
2-1+4-3+6-5+8-7+……+500-499
=(2-1)+(4-3)+(6-5)+(8-7)+……+(500-499)
=1+1+1+1+...+1 ( 共250个 1 )
=250