Завдання 1403 - 1500 » 1455-1456

1455. Обчисли: 1) 7 + (–2) = 5; 2) –5 + (–3) = –8; 3) 5 – 9 = –4; 4) –3 – (–7) = –3 + 7 = 4; 5) –4,9 · (–10) = 49; 6) –2,8 · 0,1 = –0,28; 7) 4,9 : (–10) = –0,49; 8) –3,9 : (–0,1) = 39. 1456. Виконай дії: 1) 7 + (–7) + 11 = 11; 2) –5 + (–3) + 5 = –3; 3) 4 + 7 + (–4) + (–2) = 5; 4) –2 · 50 · (–3) = 100 · 3 = 300; 5) 7 · (–12) · 0 = 0; 6) –5 · 7 · (–2) = 10 · 7 = 70.