(7: 5/6-81/9)*2 2/5: ((3/8+5/6+5/12)*8/25)=

1) 7: 5/6 = 7 * 6/5 = 42/5 = 8,4
2) 8,4 - 81/9 = 8,4 - 9 = -0,6
3) -0,6 * 2 2/5 = -0,6 * 2,4 = -1,44
4) 3/8 + 5/6 = 9/24 + 20/24 = 29/24
5) 29/24 + 5/12 = 29/24 + 10/24 = 39/24
6) 39/24 * 8/25 = 13/25
7) -1,44 : 13/25 = -144/100 * 25/13 = -36/13 = -2 10/13