MHB Proving Inequality in Mathematics: Vacation Edition

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The discussion centers on proving the inequality involving positive numbers \( a_i \) that sum to 1, specifically the inequality \( \sum_{i=1}^{n}\frac{a_{i}}{a_{i+1}}\ge\sum_{i=1}^{n}\frac{1-a_{i+1}}{1-a_{i}} \). Participants are encouraged to engage with the problem collaboratively, as the original poster is on vacation for four days. The problem is framed as a challenge for the community, emphasizing the educational aspect of tackling inequalities in mathematics. The setting is informal, allowing for a range of solutions and insights to emerge. Overall, the thread aims to foster a collaborative learning environment around this mathematical inequality.
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Re: inequality

The actual problem statement here may be written as:

Given $$a_i>0$$, $$\sum_{i=1}^n a_i=1$$ and $$a_{n+1}=a_{1}$$

Prove:

$$\sum_{i=1}^{n}\dfrac{a_{i}}{a_{i+1}}\ge\sum_{i=1}^{n}\dfrac{1-a_{i+1}}{1-a_{i}}$$

Note: Normally, when a problem is posted in this sub-forum, the OP is expected to have a solution ready to post. However, the OP did not originally post the topic here and during a staff discussion, it was felt that this sub-forum would be best as it really does not fit into any neat category. So, consider this problem a challenge for our membership as a whole. (Cool)
 
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Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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