$$5500\div(1+10\textbackslash\%)=5000$$, $$1800\div5000=36\textbackslash\%$$. 
The selling price of a sofa set is ＄$$5500$$ and the profit percentage is $$10\textbackslash\%$$ for each set sold. If the cost of the sofa set is not changed, what is the new profit percentage if raising the profit to ＄$$1800$$? 
[A] $$24\textbackslash\%$$ 
[B] $$25\textbackslash\%$$ 
[C] $$30\textbackslash\%$$ 
[D] $36\textbackslash\%$ 