a)[(12+18)x9-70]:100=
(30x9-70):100=
(270-70):100=
200:100=
2
b)314-2x[(16+5)-(83-79)]=
314-2x(21-4)=
314-2x17=
314-34=
280
c)[(8-2)x(3+2)]+100:(7+3)=
(6x5)+100:10=
30+10=
40
d)205:[(46-3x7)x2:10]=
205:[(46-21)x2:10]=
205:(25x2:10)=
205:(50:10)=
205:5=
41