In order to do this we must set up an equation
We are looking for the original amount she was paid, which we'll represent by the variable X
We know that $585 is X minus 10% of X
This means that $585 is 90% of X (or X times 0.90)
So, our equation is
X(0.90)=585
In order to solve this, we can divide both sides by 0.90
X=650
So, she was originally paid $650