– 9 = 48
57–9=(17-9)+40= = 57
57 – 7 – – 3 – – 6 –
Шаг Шаг – 7 = 50 Шаг – 2 = 48 57–9 = (57-7)-2 = 48 72
63 – 5 = 63 – 1 – 5 63 – 3 – 3 63 – – 2 – 3 63 – – 7 = 45 – 5 – 7 45 – 5 – 2 45 – – 5 – 3 45 – 4 - 3