100+99-98-97+96+95-94-93+...+8+7-6-5+4+3-2-1=?
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How to do on this four lines???
maths
2009-05-04 2:52 am
回答 (2)
2009-05-04 4:12 am
✔ 最佳答案
100+99-98-97+96+95-94-93+...+8+7-6-5+4+3-2-1=(100+99-98-97)+(96+95-94-93)+...+(8+7-6-5)+(4+3-2-1)
=4+4+..+4 <-25 terms
=25*4
=100
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#P.S.:
4,3,2,1-->4/4=1st term
8,7,6,5-->8/4=2nd term
...
100,99,98,97-->100/4=25-th term
收錄日期: 2021-04-15 16:35:46
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20090503000051KK01653