Average of Infinity: Is It Possible?

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Discussion Overview

The discussion revolves around the concept of calculating the average salary of an infinite number of workers, where each salary can be any real number between 10 and 1000. Participants explore the implications of infinity in mathematical calculations and the necessity of defining distributions for the salaries.

Discussion Character

  • Exploratory
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant suggests that without assumptions, the problem cannot be solved, proposing that one could take the lowest and highest salary to find an average or consider a finite sample from infinity.
  • Another participant argues that calculating an average requires knowing all values, which is impossible with an infinite set, and suggests using the median as a statistical indicator instead.
  • A different viewpoint states that if each worker's salary is independent, only one salary needs to be considered to determine the average.
  • One participant notes that infinity is not a number and that expressions involving infinity do not behave like those involving real numbers, suggesting that the average of infinity and one is still infinity.
  • Another participant emphasizes the need for a distribution function to calculate the average, suggesting a uniform distribution would yield an average of 505.
  • One participant proposes using limits to handle infinities, but highlights that without a defined distribution, the average remains uncertain within the range of 10 to 1000.

Areas of Agreement / Disagreement

Participants express differing views on how to approach the problem, with no consensus on a definitive method for calculating the average salary of an infinite number of workers. The discussion remains unresolved regarding the implications of infinity and the necessity of distribution definitions.

Contextual Notes

Participants note the limitations of the problem, including the lack of information about the distribution of salaries and the challenges posed by the concept of infinity in mathematical operations.

heartless
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Hello
I was watching lectures on Quantum Computing another day and I came up with a problem. I talked to my school teachers about it but everyone seemed to dodge my question except for one, my math team teacher who told me that without assuming anything it cannot be solved. Or we can take the lowest possible value and the highest, divide by 2 and that would be the average, or at last get 100 workers out of infinity and that would make an average of all.

Here's the problem:
What is the average of salaries of infinite number of workers, knowing that their salary can be any real number between 10 and a 1000?

What do you guys think about it?
Is it possible to solve it in any way? Or at least dig the problem to "average in terms of something"?

Thanks :)
 
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This looks like a definition problem. In arithmetic, you average a group by adding up all values and dividing by the number of items. If you cannot add up the values and divide by their count then you cannot calculate the average. In your scenario, adding the values is impossible since you don't know them all. Dividing by infinity is also impossible, at least arithmetically. If you try to use a notion where it does not apply then you will have problems: what is the average color of a traffic light?

The purpose of an average value is to give a statistical indicator of the position of a group of values. Here, a median point (505) gives you a fair idea of where your group is located and this may be suitable for your purpose. Considering that the set of real numbers is infinite in both directions, this position extimate can even be considered highly accurate relative to the entire set. You just use the means you need to use in order to achieve your particular purpose and disregard what does not apply.
 
If each worker's salary is independent of the salaries of other workers, you don't need to look at an infinite number of such workers. You only need to look at one.

- Warren
 
So what is the average of infinity and one? Infinity?
 
Infinity is not actually a number, so expressions involving infinity won't necessary behave like those involving real numbers. If you define an average as a sum divided by two, (infinity + 1)/2 = infinity.

- Warren
 
You have not given enough information. You also need to give the distribution function. I'm guessing you will say all salaries are equally likely. That would be called a uniform distribution. In that case it is indeed 505. No considerations of infinity are needed. As chroot said, if you asked What is the expectation value for just one salary, it would also be 505.
 
You can deal with the infinities just by taking limits as your number of workers goes to infinity. However, unless you're told some kind of distribution for the salaries, you've no idea other than it's going to be somewhere between 10 and 1000.
 

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