Remember if the Spot quote is /Euro. since is in numerator multiply interest rate of $ with spot rate and then devide by Euro interst rate bcz Euro is in denominator. The way Spot quote is given, the same way the Interest rate of the respective currency is multiplied.
e.g DC:FC = Euro: = 1.25 this suggest that FC/DC = /Euro = 1.25/1 this is the spot rate,
Interest rate Euro = 5%, Interest rate $ = 3%, Forward Rate = (1.25* 1.03)/ 1.05.
Now note that was in numerator in the Spot rate so Interest of is multiplied in numerator, since Euro is in denominator so Euro is divided in denominator. This is applicable to Direct quate as well you have to check only which cuurency is in numerator and which currency is in denominator and put the Intrst rate in the numerator or denominator accordingly to get the forward rate.