need to write a Generic methods for add,sub,mul & division operations from UI level does not matter with types like int, float or double in C#.net

I am new to Dotnet tech, Hence need ur assistence in my dotnet project.
 
I have a case study as below
 
I have a WCF service, which gives the basic calculator operations like add, subtract,Multiply and division.
 
So, in my client application, i need write the Generic Methods for all the four operations.
Hence could u pls help me out in writting Generic methods for those operation provided in serices.
Basically help me out with Generic methods & Generic Class along with generic Collection
Thanks
Chiranjeevi Yadav