## Algebra - double sales % margin

Quadratic equations and inequalities, variation equations, function notation, systems of equations, etc.
rossmurphy
Posts: 2
Joined: Mon Nov 21, 2011 5:58 am
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### Algebra - double sales % margin

Hi all,

I am trying to work out a method of calculating an item sell price using a doubled sales margin.

I have the following:

sell_price = 5.15

margin % (sell_price - buy_price / sell_price):
(5.15 - 4.15) / 5.15 = 0.2

Now I want to work out the new sell price using a % margin that is doubled. So my equation would look something like this:

(x - buy_price) / x = 0.4
(x - 4.12) / x = 0.4

Would anyone know how to solve this or if I'm doing this correctly?

rossmurphy
Posts: 2
Joined: Mon Nov 21, 2011 5:58 am
Contact:

### Re: Algebra - double sales % margin

No one has any ideas?

stapel_eliz
Posts: 1628
Joined: Mon Dec 08, 2008 4:22 pm
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No one has any ideas?
I don't know if anybody else is familiar with this finance topic. I can only say that I'm not, so I don't know the definitions and formulas you're supposed to use, so I can't say whether or not you're "doing this correctly".

As for solving, try multiplying through by "x" to clear the fraction, and then solving the resulting linear equation.