题库搜索>问题求解PS-13579
If N = 1/3 + 1/32 + 1/33, then N is between
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直接计算出N的值会比较简单，N=13/27，在确定其范围
Ariadne
放缩法，两头乘以3，分别是1/3,和1，所以8/9小于一，最接近
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2019-04-30 22:47:17
ShawnLi
最小1/3，最大不超过1。
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2018-12-23 18:02:57
Yolandaguan
1/3+1/3^2+1/3^3 = 13/27 1/2 = 13.5/27 so, 1/3 < n < 1/2
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2017-12-09 04:54:12
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