One canned juice drink is 25% orange juice; another is 5% orange juice. How many liters of each should be mixed together in order to get 20L that is 7% orange juice?
x+y=20 25%x+5%y=7%*20 => 0.25x+0.05y=1.4 miltiply every term in equaition one with 0.25: 0.25x+0.25y=5 subtract equation two from the new equation: 0.20y=3.6 y=18 x=2 2 liters of the 25% and 18 liters of the 5%
