Выполни вычисления.
12 * 70;
26 * 30;
800 − 14 * 50;
400 + 27 * 30;
900 − (17 * 20 − 640 : 2);
(324 + 18 * 30) : 8 * 9.
12 * 70 = 12 * 7 * 10 = 84 * 10 = 840;
26 * 30 = 26 * 3 * 10 = 78 * 10 = 780;
800 − 14 * 50 = 800 − 14 * 5 * 10 = 800 − 70 * 10 = 800 − 700 = 100;
400 + 27 * 30 = 400 + 27 * 3 * 10 = 400 + 81 * 10 = 400 + 810 = 1210;
900 − (17 * 20 − 640 : 2) = 900 − (340 − 320) = 900 − 20 = 880;
(324 + 18 * 30) : 8 * 9 = (324 + 18 * 3 * 10) : 8 * 9 = (324 + 54 * 10) : 8 * 9 = (324 + 540) : 8 * 9 = 864 : 8 * 9 = 108 * 9 = 972.