(5/14+10/21)×3 3/5+1 1/6: (13/22-25/33)= как можно быстрее

1) 5/14 + 10/21 = 15/42 + 20/42 = 35/42 = 5/6
2) 5/6 * 3 3/5 = 5/6 * 18/5 = 3
3) 13/22 - 25/33 = 39/66 - 50/66 = -11/66 = -1/6
4) 1 1/6 : (-1/6) = 7/6 * (-6/1) = -7
5) 3+(-7)=3-7=-4