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Timeline for Ratio of Sequences Sum Inequality

Current License: CC BY-SA 3.0

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S Apr 5, 2016 at 15:48 history suggested CommunityBot CC BY-SA 3.0
Should be $\sum a_i/b_i \ge \sum_i \left(a_i/\sum_j b_j\right) = \sum_i a_i / \sum_i b_i$.
Apr 5, 2016 at 15:18 review Suggested edits
S Apr 5, 2016 at 15:48
May 16, 2013 at 19:21 comment added Dan Stahlke Shouldn't that be $\ge$ rather than $\le$?
Dec 15, 2011 at 16:24 comment added Michael Biro Yes, I have an instance of $\sum_i a_i/(\sum_i b_i - (n-1))$, but I haven't been able to show that it's tight. I'm going to edit the question to show this.
Dec 15, 2011 at 16:24 comment added Emil Jeřábek Well, that’s tight if $\sum_ib_i< 2n-1$. If $\sum_ib_i$ is larger, it is more tricky.
Dec 15, 2011 at 16:18 comment added Emil Jeřábek I think the tight bound is $\sum_ia_i/(\sum_ib_i-(n-1))$.
Dec 15, 2011 at 16:08 comment added Michael Biro Thanks for the answer. I have that bound already, but I don't think it's tight. One of the bounds is that $b_i \geq 1$, so we can't have $b_i = \epsilon$ and $\epsilon$ close to $0$.
Dec 15, 2011 at 15:55 history answered Anthony Quas CC BY-SA 3.0