Вычисли удобным способом.
45 * (2 * 7);
720 : (9 * 2);
67 * (4 * 25);
17 * 2 * 8 * 125.
45 * (2 * 7) = (45 * 2) * 7 = 90 * 7 = 630;
720 : (9 * 2) = (720 : 9) : 18 = 80 : 2 = 40;
67 * (4 * 25) = 67 * 100 = 6700;
17 * 2 * 8 * 125 = (17 * 2) * (8 * 125) = 34 * 1000 = 34000.