4. Модуль числа - 6. Додавання цілих чисел » 204-205

204. Обчисли. а) (–15) + 12 + (–6) = –3 + (–6) = –9; б) 30 + (–9) + (–20) = 10 + (–9) = 1; в) 27 + (–12) + (–15) = 27 + (–27) = 0; 205. а) (–18) + (–14) + 16 = –2 + (–14) = –16; б) (–7) + (–9) + 16 = –16 + 16 = 0; в) (–40) + 27 + (–3) = –13 + (–3) = –16;