1. (Устно.) Вычисли.

450 - 30 * 4 + 70 / 10 = 450 - 120 + 70 = 330 + 70 = 400

280 / 7 + 160 * 5 + 70 = 40 + 800 + 70 = 840 + 70 = 910

650 + 350 - 8 = 1000 - 8 = 992

180 + 20 * 6 = 180 + 120 = 300