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The problem is formulated here. And it is also discussed here (the chosen answer to which I don't understand). I've found a few other links on this site (e.g. this), but they don't provide any explicit procedure.

My question is: what is the testing procedure for hitting the lower bound of 43 servants/rats needed to discover two poisoned objects out of 1000?

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Maybe if you wrote a detailed description of what you find confusing. I found Ori Gurel-Gurevich's answer at MO easy to understand and, up to constants, it's tight. – Louis Jan 27 '12 at 17:16
@Louis I think the OP is interested in particular in optimal solutions. – Listing Jan 27 '12 at 19:37
@Louis Yup, as Listing said, I'd appreciate a concrete, step-by-step construction for a test which can discover the two objects with only 43 rats. Furthermore, I'm not a mathematician (I'm a hobbyist) so Gurevich's answer doesn't make much sense to me at a purely mathematical level, but that's a different issue. I can at least follow a step-by-step procedure. – JasonMond Jan 27 '12 at 20:07

Look again at the following url that you mentioned in your question. Now the post has been updated with explicit procedures. You can number the wines, run the tests as specified, check the results and determine the 2 poisons. Hope that helps.

Logic problem: Identifying poisoned wines out of a sample, minimizing test subjects with constraints

Also look at Identifying 2 poisoned wines out of 2^n wines for a easier, guided explanation on how it can be solved using $6n$ tests given $2^n$ wines.

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