8. Вычисли: 980 - 900 - 1 890 - 90 + 1 699 + 1 + 30 399 + 1 + 60 749 - 40 + 1 679 - 70 + 1

Решение: 980 - 900 - 1 = 80 - 1 = 79 890 - 90 + 1 = 800 + 1 = 801 699 + 1 + 30 = 700 + 30 = 730 399 + 1 + 60 = 400 + 60 = 460 749 - 40 + 1 = 709 + 1 = 710 679 - 70 + 1 = 609 + 1 = 610