43+(-60)+12+39+(-21)=43-60+12+39-21=13
-1,23+2,14+7,38+(-5,77)+1,62=-1,23+2,14+7,38-5,77+1,62=4,14
-3/7+14/19-4/7+3 5/19=(-3/7-4/7)+14/19+62/19=-7/7+14/19+62/19=
= -1+76/19=-1+4=3
-5/18+(-4/81)+7/18+13/81=7/18-5/18+13/81-4/81=2/18+9/81=1/9+1/9=2/9
-3 5/11+1 3/8+2 5/16+(-4 6/11)=(-38/11-50/11)+(11/8+23/16)=-88/11+44/16=-8+11/4=-32/4+11/4=-21/4=-5 1/4