How to calculate percentage with string containing percentage symbol (%) in ASP.Net

hi developers,

i want  to calculate the percentage of a two values like

1. the first value is decimal = 10000

2.he first value is decimal = 10.00% (am get and bind this value from on database)

like 

TaxPercentage = 10000.00 + (10000.00 *  10.00% / 100);

the output should be like 1000.00%

i am try to done this i got error. so anyone suggest me for i am done this task.

thanking you

Paul.S