[gbrainy] Add tip to average for clarification

[Jordi Mas <jmas src gnome org>]

commit 40d5d1c6461102b4766de10e78f5f8add60ea937
Author: Jordi Mas <jmas softcatala org>
Date:   Sun May 9 09:10:46 2010 +0200

    Add tip to average for clarification

 src/Games/Calculation/CalculationAverage.cs |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/src/Games/Calculation/CalculationAverage.cs b/src/Games/Calculation/CalculationAverage.cs
index e8f7688..bdbb1ab 100644
--- a/src/Games/Calculation/CalculationAverage.cs
+++ b/src/Games/Calculation/CalculationAverage.cs
@@ -58,6 +58,10 @@ namespace gbrainy.Games.Calculation
 					GetPossibleAnswer (0), GetPossibleAnswer (1), GetPossibleAnswer (2), GetPossibleAnswer (3));}
 		}
 
+		public override string Tip {
+			get { return Catalog.GetString ("The average of a list of numbers is the sum of all of the numbers divided by the number of items in the list.");}
+		}
+
 		public override string Answer {
 			get { 
 				string answer = base.Answer + " ";