## Algebra and Trigonometry 10th Edition

$x+y=30 \\ 0.25 x+0.5 y=12$
Let $x$ and $y$ be the number of liters in the $25 \%$ solution and $50 \%$ solution, respectively. The system of two equations is: $x+y=30 \\ 0.25 x+0.5 y=12$ Substitute the value of $x=880$ into the second equation to get the value of $y$. $y=880+80$ Thus, $y=960$