proc optmodel; set Lane={'AB','BC','CA','CB'}; set Carrier={'I','II'}; number Bids{Lane,Carrier}=[ 500 525 500 475 500 525 475 500]; number MinVolume{Carrier}=[ 0 13000]; var Loads{Lane,Carrier} integer >=0 ; minimize Z=sum{i in Lane, j in Carrier}Bids[i,j]*Loads[i,j]; con LoadsperLane{i in Lane}: sum{j in Carrier}Loads[i,j]=10; con MinVol{j in Carrier}: sum{i in Lane}Bids[i,j]*Loads[i,j]>=MinVolume[j]; solve; print Loads Z; quit;