Max Product of a Set of Numbers with Sum of 100

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Discussion Overview

The discussion revolves around a mathematical puzzle concerning the maximum product of a set of numbers that sum to 100. It includes two parts: one involving non-negative real numbers and the other involving non-negative integers. Participants explore different approaches and solutions to the problem.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested, Mathematical reasoning

Main Points Raised

  • One participant introduces the puzzle, noting it has been modified from another forum.
  • Another participant questions the origin of the puzzle, suggesting it may be similar to a previously discussed thread.
  • A participant claims that the maximum product is achieved when the numbers are equal, leading to a reduction of the problem to finding the maximum of a specific function.
  • One participant asserts they have solved the puzzle, stating that the maximum value for part a) is related to the number e, while also mentioning that this knowledge is not strictly necessary for part b).
  • Another participant challenges the validity of using e in the solution for part a), arguing that the numbers must sum to 100 and that integer multiples of e cannot equal 100.
  • A participant proposes specific solutions for parts a) and b), suggesting (100/37)^37 for part a) and 4 * 3^32 for part b), while noting that these values are not fully confirmed.
  • Another participant agrees with the proposed solution for part b) and expresses confidence in the proposed solution for part a), while also raising a question about maximizing the expression xy = 100 for the highest value of x^y.

Areas of Agreement / Disagreement

Participants express differing views on the validity of certain solutions and the application of mathematical principles. There is no consensus on the final answers or methods, and the discussion remains unresolved regarding the optimal approaches for both parts of the puzzle.

Contextual Notes

Some assumptions about the nature of the numbers (real vs. integer) and the constraints of the problem are discussed, but not all mathematical steps are confirmed. The discussion includes varying interpretations of how to approach the problem.

jcsd
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I've nicked this puzzle (and slightly modified it) from another forum:

If the sum of a set of numbers is 100, what is their highest possible product if:

a) they are non-negative reals

b) they are non-negative integers
 
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jcsd said:
I've nicked this puzzle (and slightly modified it) from another forum:
Would it be from this thread?
 
No, it's not from that forum. The original puzzle only had part b) in it, part a) is my own addition, but I see that someone's already posted a very simlair puzzle.
 
Since the maximum is always achieved when the numbers are all equal, the problem reduces to finding the maximum of x100/x, and then calculating the products for the integers bracketing 100/x. The answer is x=e. I'll let you work out the final answer.
 
I've solved it already, it was meant to be a quiz.

The answer to part a) as the fact that the maximum value of x^1/x is e^1/e, is quite well known, though it's helpful for part b) it's not necessrily needed to be known.
 
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Yes but e^(100/e) is not a valid solution in this case as the numbers must add to 100, and no integer multiple if e is equal to 100. Note that the number of numbers is an integer regardless of whether or not the actual numbers themselves are constrained to be integers.

Anyway I think the solution to "part a" is (100/37)^37 and the solution to "part b" is 4 * 3^32, though I haven't totally confirmed these values.
 
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Of course yes.

well your defintely right on part b), and you certainly look right for part a)



the question I really wnated to ask for part a) I suppose was then which value of xy = 100 gives the highest vlaue for x^y.
 

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