## Algebra: A Combined Approach (4th Edition)

number of liters$\times$dye solution strength=amount of dye solution x=# of liters Liters of 20% solution = x Liters of 50% solution = 6-x Liters of 40% solution needed = 6 $0.20x + 0.50(6-x)=0.40(6)$ $0.20x + 3 - 0.50x=2.4$ $-0.30x+3=2.4$ $-0.30x=2.4-3$ $-0.30x=-0.6$ $x=-0.6\div-0.30$ $x=2$ so we need 2 liters of the 20% solution 50% solution = 6-x with x=2 50% solution =6-2=4 so we'll need 4 liters of the 50% solution.