.20 X + 0.05y = .10 (30) <span>Solve the first equation for X: </span> <span>X = 30 - y </span> <span>Substitute this value for X into the second equation: </span> <span>.20 (30 - y) + 0.05y = .10 (30) </span> <span>Expand: </span> <span>6 - .2y + 0.05y = 3 </span> <span>Combine like terms: </span> <span>.15y = 3 </span> <span>Divide by .15: </span> <span>y = 20 fluid oz </span> <span>Substitute this value for y into X = 30 - y and solve for X: </span> <span>X = 10 fluid oz.</span>