USANDO LINGO

min=500*x1+900*x2+1000*y1+2000*y2;

20*x1+50*x2>=120;

30*x1+35*x2>=150;

40*x1+45*x2>=200;

x1<=7*y1;

x2<=7*y2;

@bin(y1);

@bin(y2);

@gin(x1);

@gin(x2);