1) -9+(-28)-(27)=9-28-27=-64
2) 20-(-9)-9=20+9-9=20
3) -16-(-30)+(-30)=-16
4) -12-8+(-10)=-12-8-10=-30
1) -9+(-28)-(27)=9-28-27=-64
2) 20-(-9)-9=20+9-9=20
3) -16-(-30)+(-30)=-16
4) -12-8+(-10)=-12-8-10=-30