Answer:
Georgina should add 3 liters of 49% citric acid solution.
Step-by-step explanation:
let x be the liters of 49% solution that Georgina should add. Then after she has added 0.5 liters of water, the total liters of solution she has will be
[tex]x+0.5[/tex]
and 42% of this should be the solute:
[tex]0.42(x+0.5)[/tex]
and since adding water does not add any solvent, this amount must come from the 49% citric acid solution; therefore
[tex]0.42(x+0.5)=0.49x[/tex]
Solving for [tex]x[/tex] we get:
[tex]\boxed{x= 3\:liters}[/tex]
This the amount of 49% citric acid solution Georgina must add.
