Помогите решить 4 7/10-2 8/15+1 11/20
4 7/10 - 2 8/15 + 1 11/20 = 3 целых 43/60
1) 4 7/10 - 2 8/15 = 4 21/30 - 2 16/30 = 2 5/30 = 2 1/6
2) 2 1/6 + 1 11/20 = 2 10/60 + 1 33/60 = 3 43/60