Тисяча. Нумерація трицифрових чисел » 453

64 : 8 • 9 = 8 • 9 = 72 (81 – 18) : 9 = (81 – 11 – 7) : 9 = (70 – 7) : 9 = 63 : 9 = 7 18 : 9 + 2 • 8 = 2 + 16 = 18 8 • 7 + 45 : 5 = 56 + 9 = 56 + 4 + 5 = 60 + 5 = 65 72 : (13 – 5) = 72 : (13 – 3 – 2) = 72 : (10 – 2) = 72 : 8 = 9 60 – 40 : 5 = 60 – 8 = 52