Solution A is 30% alcohol and solution B is 60% alcohol. How much of each is needed to make 80 liters of a solution that is 45% alcohol?
please help.
Call the amount of each solution needed $\displaystyle x$ and $\displaystyle y$ (measured in liters). We know that if we combine these two amounts, we should get a total of 80 liters, so
$\displaystyle x + y = 80$.
We also know that we want our final solution to be 45% alcohol, so
$\displaystyle 0.30x + 0.60y = 0.45\cdot80$.
Solve for $\displaystyle x$ and $\displaystyle y$.