Chapter 6 - Systems of Equations and Inequalities - 6-4 Application of Linear Systems - Practice and Problem-Solving Exercises - Page 387: 23

66.67 mL of 5% acetic acid and 133.33 mL of 6.5% acetic acid

$x+y = 200$ $.05x+.065y = .06(200)$ $x+y = 200$ $x+y-y = 200-y$ $x = 200-y$ $.05x+.065y = .06(200)$ $.05*(200-y)+.065y = .06(200)$ $10 - .05y + .065y = 12$ $10 + .015y = 12$ $10 + .015y -10 = 12-10$ $.015y = 2$ $.015y/.015 = 2/.015$ $y = 400/3$ $x+y = 200$ $x + 400/3 = 200$ $x + 400/3 = 600/3$ $x + 400/3 -400/3 = 600/3 - 400/3$ $x = 200/3$