$$28 * 6 = 168$$
$$48 * 4 = 192$$
$$112 * 8 = 896$$
$$125 * 3 = 375$$
$$230 * 4 - 400 = 920 - 400 = 520$$
$$240 * 2 : 6 = 480 : 6 = 80$$
$$280 - 490 : 7 = 280 - 70 = 210$$
$$180 : 3 : 5 = 60 : 5 = 12$$