a). [20+2×(110-20)]:10+2×2=
=[20+2×90]:10+2×2=
=(20+180):10+2×2=
=200:10+2×2=
=20+4
=24
b). [72:(8×2-40:5)+91]:(7+3)=
=[72:(16-8)+91]:10=
=[72:8+91]:10=
=(9+91):10=
=100:10=
=10
c). 200+30×[9×(8+4):4]-880:10=
=200+30×[9×12÷4]-880:10=
=200+30×(9×3)-880:10=
=200+30×27-880:10=
=200+810-88=
=1010-88=
=922
d).16×[40+2×(560:8-7×7)×(10-100:10)=
=16×[40+2×(70-49)×(10-10)=
=16×[40+2×21×0]=
=16×(40+42×0)=
=16×(40+0)=
=16×40=
=640
e). 1000+8×[(56:7+12)×101-2000]:2=
=1000+8×[(8+12)×101-2000]:2=
=1000+8×[20×101-2000]:2=
=1000+8×(2020-2000):2=
=1000+8×20:2=
=1000+8×10=
=1000+80
=1080
