diff --git a/lib/team_ferwin.rb b/lib/team_ferwin.rb
index 90ea37d..52b00e8 100644
--- a/lib/team_ferwin.rb
+++ b/lib/team_ferwin.rb
@@ -2,18 +2,25 @@ class TeamFerwin
 
     ROMAN_NUMERALS = {
       "I" => 1,
+      "IV" => 4,
       "V" => 5,
+      "IX" => 9,
       "X" => 10,
+      "XV" => 40,
       "L" => 50,
+      "XC" => 90,
       "C" => 100,
+      "CD" => 400,
       "D" => 500,
+      "CM" => 900,
       "M" => 1000
     }
     # Use this method to convert roman numbers to arabic
     #
     # Don't you dare cheat on spec!!!
-    def initialize(roman)
+    def initialize(roman, mode)
       @roman_numeral_tokens = roman
+      @mode = mode.to_sym
     end
 
     def to_i
@@ -32,27 +39,33 @@ def to_i
     end
 
     def to_roman(num)
+      roman = ""
+      ROMAN_NUMERALS.each_pair.to_a.reverse.each do |token, digit|
+        while num >= digit do
+          roman << token
+          num -= digit
+        end
+      end
 
+      roman
     end
 
-    def +(other)
-      self.to_i + other.to_i
-    end
-
-    def -(other)
-      self.to_i - other.to_i
-    end
-
-    def /(other)
-      self.to_i.to_f / other.to_i.to_f
-    end
-
-    def *(other)
-      self.to_i * other.to_i
+    [:+, :-, :*, :**, :/, :%].each do |op|
+      define_method op do |other|
+        result(self.to_i.send(op, other.to_i))
+      end
     end
 
     private
       def arabic(token)
         ROMAN_NUMERALS[token]
       end
+
+      def result(num)
+        if @mode == :roman
+          self.to_roman(num)
+        else
+          num
+        end
+      end
 end