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Is this a weighted average/percentage problem?
Let's say a Marketing company has a total turnover of 10000 \$
There are 3 salesmen A,B,C with the following turnovers:
The turnovers have two components - Income and Expenses:
A = 2000 $
B = 3000 $
C = 5000 $
Ia = 80% = 1600 $
Ib = 70% = 2100 $
Ic = 60% = 3000 $
Ea = 20% = 400 $
Eb = 30% = 900 $
Ec = 40% = 2000 $
Total Income = 6700 USD = 67%
Total Expense = 3300 USD = 33%
Now, If the company wants to increase total Income by 10 %, How should this increase be split across the Incomes of A,B,C? Is this a weighted average/percentage increase problem?
Firstly, this is a duplicate of your other question. Secondly, it has the same answer: if you want to increase the income, which is at 6700, by 10%, then adding 670 income to the three in any particular way will do it. If you wanted to maintain the income/expense ratio for each person, then it is slightly less trivial.
In this case, you want $0.8 A_+ + 0.7 B_+ + 0.6 C_+ = 670$. Here, I use letter$_+$ to indicate the additional turnover to the person with that letter. In a sense, that's a weighted average problem... but that's not how I would solve it (I would do it as above).