Could use a little help please: want to avoid elimination process

[Josh260893]

So basically I'm trying to figure out a way to create a number to reach a certain percentage from a currently reached percentage.

I have this equation so far (Pretty basic):

3.7 - 1.25 = 2.45

2.45/3.7 = 0.66216216216 recurring or 66%

But what i want is to achieve this using that same equation layout and without using the process of elimination

x - 1.25 = y

y/x = 0.75

Is this possible or not?

And if so would the answer still be 0.75 if the value 1.25 was to change

 

[Deleted member 4993]

So basically I'm trying to figure out a way to create a number to reach a certain percentage from a currently reached percentage.

I have this equation so far (Pretty basic):

3.7 - 1.25 = 2.45

2.45/3.7 = 0.66216216216 recurring or 66%

But what i want is to achieve this using that same equation layout and without using the process of elimination

x - 1.25 = y

y/x = 0.75

Is this possible or not?

And if so would the answer still be 0.75 if the value 1.25 was to change

I do not understand your problem very well.

Can you explain - why do you want to do this?

That may explain what and how better!

 

[Josh260893]

its to figure out how to achieve a certain GP on a bar. and instead of working out the selling price using the process of elimination to guess at what price it should be sold at

 

[DrPhil]

So basically I'm trying to figure out a way to create a number to reach a certain percentage from a currently reached percentage.

I have this equation so far (Pretty basic):

3.7 - 1.25 = 2.45

2.45/3.7 = 0.66216216216 recurring or 66%

But what i want is to achieve this using that same equation layout and without using the process of elimination

x - 1.25 = y

y/x = 0.75

Is this possible or not?

And if so would the answer still be 0.75 if the value 1.25 was to change

You have two equations in two unknowns, so it is very likely a solution exists. Elimination of one of the variables is a standard method for solving such a. system:
x - 1.25 = 0.75x --> 0.25x = 1.25, x = 5.

If you replace "1.25" by a symbolic parameter, you could solve for x as a function y and the percentage and the parameter.

 

[Josh260893]

You have two equations in two unknowns, so it is very likely a solution exists. Elimination of one of the variables is a standard method for solving such a. system:
x - 1.25 = 0.75x --> 0.25x = 1.25, x = 5.

If you replace "1.25" by a symbolic parameter, you could solve for x as a function y and the percentage and the parameter.

This worked a treat. changing the vale from 1.25 to anything else then dividing x by 0.25 left it with 0.75 all the time no matter what the known value was.

I literally spent hours working through possibilities with no success.