1) 162 * 54 + 12 * 18 + 88 * 18 + 162 * 46 =
= 162 * (54 + 46) + 18 * (88 + 12) =
= 162 * 100 + 18 * 100 = 16200 + 1800 = 18000 ;
2) 15 * 34 - 15 * 14 + 10 * 25 - 15 * 10 + 10 * 75 =
= 15 * (34 - 14) + 10 * (25 - 15 + 75) = 15 * 20 + 10 * 85 = 300 + 850 = 1150.