A solvent producer manufactures a product with the following requirements: combustion point specific weight content content The product may be made from three possible ingredients. A, B and C which cost 20 cents, 19 cents and 25 cents per liter, respectively. These ingredients have the following characteristics which can be assumed to combine linearly: A combustion point specific weight content (% by vol.) content (% by vol.) 260 0.93 7 3 B 250 1.08 260 1.00 8% by volume 4% by volume 6 5 C 270 0.96 9 4 The manufacturer would like to make the product (subject to the above requirement) at minimum cost. Formulate the problem as a linear programming model.