Excel c# convert cell to percentage

Question

I need to convert a cell with a double to a precentage. I used a macro in excel and it says:

Range(\"B5\").Select
Selection.Style = \"Percent\"

Answer 1

I've found the anwser with help of JN Web

Excel.Range procentRange = xlWorksheet.get_Range("A1","A1");    
procentRange.NumberFormat = "###,##%";

So first you need a range, then set the decimals and add "%" -> automatically a 100 time multiplication