In this task you will be given an arithmetic operation in Italian and you have to find its answer. The operations 'addition' and 'subtraction' have been replaced with their italian translations i.e you need to perform addition when you see 'aggiunta' and subtraction in case of 'sottrazione'.
Q: 6336 sottrazione 7831 aggiunta 4628 sottrazione 3909 aggiunta 6404
A: 
5628