4. Вычисли и проверь решение. 61-32 17 + 29 35-18 47 + 26

1. $$61 - 32 = 29$$ 2. $$17 + 29 = 46$$ 3. $$35 - 18 = 17$$ 4. $$47 + 26 = 73$$ **Решение:** 1. $$61 - 32 = (61 - 30) - 2 = 31 - 2 = 29$$ Проверка: $$29 + 32 = 61$$ 2. $$17 + 29 = (17 + 3) + (29 - 3) = 20 + 26 = 46$$ Проверка: $$46 - 29 = 17$$ 3. $$35 - 18 = (35 - 15) - 3 = 20 - 3 = 17$$ Проверка: $$17 + 18 = 35$$ 4. $$47 + 26 = (47 + 3) + (26 - 3) = 50 + 23 = 73$$ Проверка: $$73 - 26 = 47$$