ELISHEVA,
It would appear GrandFather has already provided an an example. 
40 units at value of 1
10 units at value of 2
10 units at value of 4

60 units total with a value of 100 and an average of 1 + 2/3

Problem:  Divide into 2 groups of 30
Group A & B both have 30 units with exactly 1.67 (1 + 2/3)
20 units of 1
5 units of 2
5 units of 4

[download]
Now assuming you don't have any bugs in your code and GrandFather used it correctly, it can be shown that it does not always produce optimal results. Update: To give you an idea of how I was going to find such a scenario - see Re: Permutation of groups (and the root thread).

Cheers - L~R

In reply to Re^5: Average Price Algorithm by Limbic~Region
in thread Average Price Algorithm by camelcom

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