a) $\frac{-315}{702}$ = $\frac{-315:3}{702:3}$
=$\frac{-105}{234}$ =$\frac{-105:3}{234:3}$
=$\frac{-35}{78}$
Vậy $\frac{-315}{702}$ = $\frac{-35}{78}$
b) $\frac{-3112}{-9336}$ = $\frac{3112}{9336}$ = $\frac{3112:2}{9336:2}$ = $\frac{1556}{4668}$
= $\frac{1556:2}{4668:2}$ =$\frac{778}{2334}$
=$\frac{778:2}{2334:2}$ = $\frac{389}{1167}$
=$\frac{389:389}{1167:389}$ =$\frac{1}{3}$
Vậy $\frac{-3112}{-9336}$=$\frac{1}{3}$
