(12 1/2 - 2) : (1/5 - 1/40) - (2 + 6 2/3) : (1 5/6 - 1 2/3) * 3/8 = 40 1/2
1) 12 1/2 - 2 = 10 1/2
2) 1/5 - 1/40 = 8/40 - 1/40 = 7/40
3) 2 + 6 2/3 = 8 2/3
4) 1 5/6 - 1 2/3 = 1 5/6 - 1 4/6 = 1/6
5) 10 1/2 : 7/40 = 21/2 * 40/7 = 3 * 20 = 60
6) 8 2/3 : 1/6 = 26/3 * 6 = 26 * 2 = 52
7) 52 * 3/8 = 156/8 = 19 4/8 = 19 1/2
8) 60 - 19 1/2 = 59 2/2 - 19 1/2 = 40 1/2