MAX 600x1t + 450x1f + 300x1a + 600x2t + 450x2f + 300x2a + 600x3t + 450x3f+ 300x3a        	                                                                            
ST
x1t + x2t + x3t <= 900                                 	
x1f + x2f + x3f <= 700                                  
x1a + x2a + x3a <= 1000                                 
x1t + x1f + x1a >= 300                                  
x2t + x2f + x2a >= 480                                  
x3t + x3t + x3a >= 420                                  
x1t + x1f + x1a <= 500                                  
x2t + x2f + x2a <= 800		              			
x3t + x3f + x3a <= 700   
800x1t - 500x2t = 0                               
700x1t - 500x3t = 0                               
800x1f - 500x2f = 0                               
700x1f - 500x3f = 0                               
800x1a - 500x2a = 0                                
700x1a - 500x3a = 0