-2 11/12+ (-6 5/8)= ? -2/7 + 5/12=? -4/9 + (-3/5)=? 1+(-7/15)=? X-3,21=-7,15=?

Question

-2 11/12+ (-6 5/8)= ? -2/7 + 5/12=? -4/9 + (-3/5)=? 1+(-7/15)=? X-3,21=-7,15=?

Answer 1

-2 11/12+(-6 5/8)=-(2 22/24+6 15/24)=
=-8 37/24=-9 13/24;

-2/7+5/12=35/84-24/84=11/84;

-4/9+(-3/5)=-(20/45+27/45)=
=-47/45= -1 2/45;

1+(-7/15)=15/15-7/15=8/15;

x-3,21=-7,15;
x=-7,15+3,21;
x=-3,94.