Yes correct...
Try this query small changes
Declare @x as numeric(19,6)
Set @x = convert(float, ($[$38.U_DiscAmount.number])) / ($[$38.14.number])
Select round(cast(@x as float) *100,4)
or
Declare @x as numeric(19,6)
Set @x = round(convert(float, ($[$38.U_DiscAmount.number])) / ($[$38.14.number]),4)
Select cast(@x as float) *100
Hope solves