来自何心怡的问题
计算:1-2+3-4+5-…-98+99=______.
计算:1-2+3-4+5-…-98+99=______.
1回答
2020-02-28 00:04
计算:1-2+3-4+5-…-98+99=______.
计算:1-2+3-4+5-…-98+99=______.
1-2+3-4+5-…-98+99,
=(1-2)+(3-4)+(5-6)+…+(97-98)+99,
=(-1)×49+99,
=50.
故答案为:50.