Find the 9 Values of a Set of Positive Integers

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Discussion Overview

The discussion revolves around finding a set of nine different positive integers whose arithmetic mean is 123456789. Each integer is required to have a different number of digits, with the largest being a nine-digit number. The focus is on exploring potential solutions and the reasoning behind them.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant suggests a specific set of numbers: 9, 99, 999, 9999, 99999, 999999, 9999999, 99999999, 999999999.
  • Another participant questions how this solution is derived.
  • A different participant proposes that uniqueness in the solution may depend on certain maximality or minimality conditions, referencing the maximum number of 999,999,999.
  • It is noted that 123456789 can be expressed as a sum of numbers with increasing digits, specifically as 1 + 11 + 111 + 1111 + ... + 111111111, suggesting a method to find the integers by multiplying by 9.
  • There is an assertion that the values must be maximal under the given constraints, implying a singular correct answer.

Areas of Agreement / Disagreement

Participants express differing views on the uniqueness of the solution and the methods to derive the integers. While some suggest a specific set of numbers, others question the reasoning and explore alternative interpretations, indicating that the discussion remains unresolved.

Contextual Notes

The discussion includes assumptions about the nature of the integers and their digit counts, as well as the implications of maximality and minimality conditions that are not fully explored or agreed upon.

PrudensOptimus
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The arithmetic mean of a set of nine different positive integers is 123456789. Each number in the set contains a different number of digits with the greatest value being a nine-digit number. Find the value of each of the nine numbers .
 
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9,99,999,9999,99999,999999,9999999,99999999,999999999
 
how?
 
The only conceivable way there could be a unique answer is if all the numbers involved had some maximality/minimality conditions imposed on them (ias x+y=x-1+y+1, then any unqueness here must expliot some maximality of y or minimality of x; we have a maxmial number 999,999,999) . By inspection one sees that 123456789*9 can only be the sum of numbers satisfying your conditions if they are maximal wrt the constraints.

Also it's clear that 123456798
=1+11+111+1,111+...111,111,111, which should give another hint
 
I immediately recognized that 123456789 = 1+11+111+1111...111111111, like Grime said. Knowing this, multiply both sides by 9, and find the answer.

Also like Grime said, the values must be that maximums, which means that there is only one correct answer.
 

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