/* Objective function */
min: 22 x1 + 20 x2 + 18 x3;

/* Variable bounds */

bel: 6 x1 + 3 x2 + 4 x3 >= 120;
ugh: 2 x1 + 3 x2 + 4 x3 >= 42;
mas: 2 x1 + 5 x2 + 4 x3 >= 48;