diff --git a/Koans/src/test/scala/org/functionalkoans/forscala/Flight03.scala b/Koans/src/test/scala/org/functionalkoans/forscala/Flight03.scala
index e12a6fe..34d10d0 100755
--- a/Koans/src/test/scala/org/functionalkoans/forscala/Flight03.scala
+++ b/Koans/src/test/scala/org/functionalkoans/forscala/Flight03.scala
@@ -4,7 +4,7 @@ import support.BlankValues._
 import support.KoanSuite
 
 class Flight03 extends KoanSuite with ShouldMatchers {
-
+  
   // Flight 03 exercise - uncomment the tests below, and then define a class
   // called ComplexNum that:
   // 1. Has class parameters real and imaginary
@@ -21,10 +21,25 @@ class Flight03 extends KoanSuite with ShouldMatchers {
   // The tests below should exercise all of these requirements although they
   // are far from exhaustive
 
-  // class ...
+  class ComplexNum( val real: Double, val imaginary:  Double ) {
+    def this( real: Double ) { this( real, 0d) }
+    
+    override def toString = this.imaginary match {
+                              case x: Double if(x < 0) =>  real + " - " + math.abs(imaginary) + "i" 
+                              case x: Double => real + " + " + imaginary + "i" 
+                            }
+    
+    def +( other: ComplexNum ) : ComplexNum = { 
+      new ComplexNum( this.real + other.real, this.imaginary + other.imaginary )
+    }
+    
+    def +( num: Double ) = new ComplexNum( this.real + num, this.imaginary )
+  }
+  
+  implicit def double2ComplexNum( double: Double ) = new ComplexNum( double )
 
   // UNCOMMENT BELOW
-  /*test ("Create a new Complex number and check the values for the real/imaginary parts") {
+  test ("Create a new Complex number and check the values for the real/imaginary parts") {
     val complex = new ComplexNum(4, 2)
 
     complex.real should be (4)
@@ -67,32 +82,31 @@ class Flight03 extends KoanSuite with ShouldMatchers {
 
     complex.real should be (12)
     complex.imaginary should be (3.2)
-  }
-  */
+  }  
   // Extra credit - numbers with a negative imaginary part should be output
   // as 6.0 - 5.0i instead of 6.0 + -5.0i - if you have time, write a new test
   // for this outcome, and then adapt the toString in the class to work correctly
   // Hint: scala.math.abs will give the absolute value of a double
-
+  
   // UNCOMMENT BELOW
-  /*test ("Format for negative imaginary part should be R.R - I.Ii") {
+  test ("Format for negative imaginary part should be R.R - I.Ii") {
     val complex = new ComplexNum(5, -6)
     val complex2 = new ComplexNum(5.5, -6.6)
 
     complex.toString should be ("5.0 - 6.0i")
     complex2.toString should be ("5.5 - 6.6i")
-  }*/
+  }
 
   // Extra extra credit - adding a double to a complex works, but adding a complex
   // to a double does not. If you add an implicit conversion you can make this work
   // if you have time, write a test, and add an implicit to make it work
 
   // UNCOMMENT BELOW
-  /*test ("Add a complex to a double") {
+  test ("Add a complex to a double") {
     val complex = 5.6 + new ComplexNum(3.4, 4.5)
 
     complex.real should be (9)
     complex.imaginary should be (4.5)
-  }*/
+  }
 }