2005-1-11-21-31-…-181-191=_.
问题描述:
2005-1-11-21-31-…-181-191=______.
答
2005-1-11-21-31-…-181-191
=2005-(1+11+21+31+…+181+191)
=2005-(1+191)×20÷2
=2005-192×10
=2005-1920
=85
故答案为:85.