1) - + ( = -
2) 4/7 - (5/11-3/7) = 4/7-2/77=6/11
3) 3 5/6 + (-5/6-1/7) = 23/6+(-41/42)=23/6-41/42=20/7
4) 3/8 - (1/9 - 5/8) = 3/8 - (-37/72)=3/8+37/72=8/9
5) 2 3/4 - (1 1/4 + 5 1/2) = 11/4 - (1+5+(1/4+1/2)) = 11/4 - (6+ 3/4) = 11/4 - 6 3/4= 11/4 - 27/4 = -4
6) 6 5/8 - (1 3/4 - 2 3/8) = 53/8 - (7/4 - 19/8)= 53/8 - (-5/8) = 53/8 + 5/8 = 29/4
Там где / это дробь)))