1) (3/4+5/6):(1целая1/2-3/5)×1целая8/19-(1-7/8)×4=2
9+10/12:(3/2-3/5)×27/19- 8-7/8×4
19/12:15-6/10×27/19-1/8×4
1/12:9/10×27-1/2
1/12×10/9×27-1/2
1/6×5×3-1/2
1/2×5-1/2
5/2-1/2
5-1/2
4/2=2
2)(3целых2/3-1целая7/9):(1/2-1/4)+(2целых1/2+1целая3/4)×(3/34+2/14):9/56=13целых167/168
(11/3-16/9):2-1/4+(5/2+7/4)×(3/34+1/7)×59/9
33-16/9:1/4+10+7/4×21+34/238×59/9
17/9×4+17/4×55/238×59/9
68/9+1/4×55/14×59/9
68/9+3245/504
3808+3245/504
7053/504
2351/168=13целых167/168