3) (15 1/3-8 5/18)×2 4/7 ÷ 6 1/21 - 2 5/8=

4) 8,25 ÷ 1,1 - (3-2,8× 3/7) ÷0,6=

2-0,7(3х-4)=3(0,3+11,6)                   2-2,1x+2,8=3*11,94,8-2,1x=35,7x=(35,7-4,8)/-2,1x=-103/78,25 ÷ 1,1 - (3-2,8× 3/7) ÷0,67,5-(3-1,2)/0,67,5-1,8/0,67,5-34,5