а)2 4/15+1 5/6
б)4 7/10-1 8/15
в)8 3/8-(5 5\6+1 3/4)

а)2 4/15+1 5/6=3 8/30+25/30= 3 33/30= 3 11/10= 4 1/10= 4,1б)4 7/10-1 8/15=3 21/30-16/30= 3 5/30= 3 1/6в)8 3/8-(5 5\6+1 3/4)=8 3/8-(6 10/12+9/12)= 8 3/8-6 19/12= 67/8-91/12= 201/24-182/24= 19/24