1/2 -(+4)=1/2-4=-3 1/2

-5/11-(-5/11)=-5/11+5/11=0

-5-(2 цел 1/3)=-5-2 1/3=-7 1/3

-8-(-1/7)=-8+1/7=-7 6/7

1/6-(+3)  =1/6-3=-2 5/6

-5/12 -(-4)=-5/12+4=3 7/12