1. 2(3+4) x 3(20 - 10) =
6 + 8 х 60 - 30 = 14 х 30 = 420
2. 12 х 12 + (100 + 36) х 3 =
144 + 136 х 3 = 144 + 408 = 552
3. 22 х 35 - (500 + 200) =
770 - 700 = 70
4. 25 х 31 + 2(30 - 20) =
775 + 60 - 40 = 795
5. 602 : (150 х 2 + 1) х (16 + 15) =
602 : 301 х 31 = 62