(12 2/3 - 63 1/3 : 5,(18)) * (2,25 + 2 2/3 : 1 1/15) * 6 : 1,5 = 8 4/9
1) 63 1/3 : 5,(18) = 190/3 : 57/11 = 190/3 * 11/57 = 2090/171 = 110/9 = 12 2/9
2) 12 2/3 - 12 2/9 = 12 6/9 - 12 2/9 = 4/9
3) 2 2/3 : 1 1/15 = 8/3 : 16/15 = 8/3 * 15/16 = (1*5)/(1*2) = 5/2 = 2,5
4) 2,25 + 2,5 = 4,75 = 4 3/4 = 19/4
5) 4/9 * 19/4 = 19/9
6) 19/9 * 6 = 19/3 * 2 = 38/3
7) 38/3 : 1,5 = 38/3 : 3/2 = 38/3 * 2/3 = 76/9 = 8 4/9