Hello Sebastião,
In Group 4 exercise 2, you first need to find the MFC for the period through the information given on the exercise. You know that the UROH under FCPC is 180 000€, meaning;
180 000€ = MFC * (1 - 15000/33000). Solving this equation you find that MFC for the period are 330 000 €
Than, you need to analyse the difference in profits between the different systems to find how many units are in closing inventories. You can find that the MFC/unit = 330 000 € / 15 000 = 22€/unit. The difference in profits between TFC and VC can be derived from the MFC of the unsold units, meaning:
34 000€ - 23 000€ = FG Closing * 22€
FG Closing = 500 units
Good study!