75 : 5 = (50 + 25) : 5 = 50 : 5 + 25 : 5 = 10 + 5 = 15
75 : 3 = (60 + 15) : 3 = 60 : 3 + 15 : 3 = 20 + 5 = 25
42 : 3 = (30 + 12) : 3 = 30 : 3 + 12 : 3 = 10 + 4 = 14
42 : 2 = (30 + 12) : 2 = 30 : 2 + 12 : 2 = 15 + 6 = 21
