Soluzione del esercizio 108 di Matematica.blu: Algebra, Geometria, Statistica, Vol. 1

$13-\{120-[(35+5):8+20:(7-3)]\}:11$ $=$ $13-\{120-[(40):8+20:(4)]\}:11$ $=$ $13-\{120-[(5)+(5)]\}:11$ $=$ $13-\{120-[10]\}:11$ $=$ $13-\{110\}:11$ $=$ $13-\{10\}$ $=$ $3$