Im pretty sure its 18 unless im reading it wrong
        
                    
             
        
        
        
A. The hexagon as the series is adding a side each time. So you started with 3, 4, 5...
        
                    
             
        
        
        
-12 n - 24 = -12 (n+2) 
-12 (n+2)  is the answer
        
                    
             
        
        
        
To solve this, you would divide 478 by 18, which equals 26.5555556. Since you can't have half a package of paper, the answer would be 26. Hope this helps!