Reversing Averages: Extracting Info from an Average

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Extracting specific counts of individual inputs from an average is not straightforward because many combinations can yield the same average. For example, different sets of numbers can produce the same mean, demonstrating the loss of detail when averaging. However, since the inputs are constrained to whole numbers between 1 and 5, the number of combinations is limited. This scenario relates to the theory of partitions in number theory, which explores how to express a number as the sum of whole numbers. Understanding this theory can provide insights into the possible combinations that lead to a given average.
fightstacy
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Hello!

I was wondering if anyone had an effective way of extracting information from an average.

I have a list of averages, they're acquired from inputs from 1 - 5, ..and I can see the amount of inputs used to get the average.

An example would be

60 inputs within the range 1 - 5
Average = 2.88

Is there a way to extract how many 1's 2's 3's 4's and 5's were used to get the average from this information?

Thanks in advance!
 
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No. There are many combinations of numbers that produce the same average.
 
Number Nine said:
No. There are many combinations of numbers that produce the same average.

Could I get all possibilities?
 
fightstacy said:
Could I get all possibilities?
No.

When you take the average (mean) of a set of numbers, you lose detail about the numbers.

Suppose you have a very simple set of numbers: {1, 2, 3}. The mean of this set of numbers is 2. This set, {1.1, 2, 2.9} also has a mean of 2, as does {1.01, 2, 2.99}. Any set of three numbers that add up to 6 would have a mean of 2.
 
Mark44 said:
No.

When you take the average (mean) of a set of numbers, you lose detail about the numbers.

Suppose you have a very simple set of numbers: {1, 2, 3}. The mean of this set of numbers is 2. This set, {1.1, 2, 2.9} also has a mean of 2, as does {1.01, 2, 2.99}. Any set of three numbers that add up to 6 would have a mean of 2.

The thing is though, ..that the range 1 - 5 is whole numbers only, no fractions. ..this would surely decrease the amount of possibilities to few, ..am I wrong?
 
fightstacy said:
The thing is though, ..that the range 1 - 5 is whole numbers only, no fractions. ..this would surely decrease the amount of possibilities to few, ..am I wrong?
You are right. You want to know how many ways there are to express N as the sum of M whole numbers. This is the sort of thing that is studied in the theory of partitions, a branch of number theory. See here for more:

http://en.wikipedia.org/wiki/Partition_(number_theory)
 
jbunniii said:
You are right. You want to know how many ways there are to express N as the sum of M whole numbers. This is the sort of thing that is studied in the theory of partitions, a branch of number theory. See here for more:

http://en.wikipedia.org/wiki/Partition_(number_theory)

Thanks for that Jbunniii, looks like a fun read!
 
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