Răspuns :

Salut! :)

a) a × b × c × d = 12 × 30 = 360

b) 7ac - 2bd = 7 × 12 - 2 × 30 = 84 - 60 = 24

c) 15ac : 2bd = 15 × 12 : 2 × 30 = 180 : 2 × 30 = 90 × 30 = 2700