急急急！！！！！用lingo求解线性规划问题出现错误 求高手解答~~~谢谢

max=1000*(x11+x12+x13)+700*(x21+x22+x23)+600*(x31+x32+x33);
(8*x11+6*x21+5*x31)<=2/3*(1+0.15)*(8*x12+6*x22+5*x32);
(8*x11+6*x21+5*x31)>=2/3*(1-0.15)*(8*x12+6*x22+5*x32);
(8*x13+6*x23+5*x33)<=1/2*(1+0.15)*(8*x12+6*x22+5*x32);
(8*x13+6*x23+5*x33)>=1/2*(1-0.15)*(8*x12+6*x22+5*x32);
(8*x11+6*x21+5*x31)<=4/3*(1+0.10)*(8*x13+6*x23+5*x33);
(8*x11+6*x21+5*x31)>=4/3*(1-0.10)*(8*x13+6*x23+5*x33);
8*x11+6*x21+5*x31<=2000;
8*x12+6*x22+5*x32<=3000;
8*x13+6*x23+5*x33<=1500;
10*x11+5*x21+7*x31<=4000;
10*x12+5*x22+7*x32<=5400;
10*x13+5*x23+7*x33<=1500;
x11+x12+x13<=600;
x21+x22+x23<=1000;
x31+x32+x33<=800;
@gin(x11);@gin(x12);@gin(x13);@gin(x21);@gin(x22);@gin(x23);@gin(x31);@gin(x32);@gin(x33);