题目内容
0.1+0.3+0.5+0.7+0.9+0.11+0.13+0.15+0.17+0.19+0.21+…+0.99=分析：此题分两部分计算，一部分为0.1+0.3+0.5+0.7+0.9，另一部分为0.11+0.13+0.15+0.17+0.19+0.21+…+0.99
，这两部分都可运用高斯求和公式进行简算．
，这两部分都可运用高斯求和公式进行简算．
解答：解：0.1+0.3+0.5+0.7+0.9+0.11+0.13+0.15+0.17+0.19+0.21+…+0.99
=（0.1+0.9）×5÷2+（0.11+0.99）×45÷2
=2.5+24.75
=27.25
故答案为：27.25．
=（0.1+0.9）×5÷2+（0.11+0.99）×45÷2
=2.5+24.75
=27.25
故答案为：27.25．
点评：仔细观察题目中数字构成的特点和规律，运用高斯求和公式，进行简便计算．
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