a) 2+2×2=
=2+4=
=6
b) 3+7×10=
=3+70=
=73
c) 9-8:4=
=9-2=
=7
d) 100-100:10=
=100-10=
=90
e) 14+16:4-9=
=14+4-9=
=18-9=
=9
f) 12:4+9:3=
=3+3=
g) 8+8:8-8=
=8+1-8=
=9-8=
=1
h) 12+18:6×4=
=12+3×4=
=12+12=
=24
i) 2+(2×2:2-2)+840-40×0=
=2+(4:2-2)+840-0=
=2+(2-2)+840-0=
=2+0+840-0=
=2+840=
=842
j) 44-[5+1+3×(4-7:7)]:3=
=44-[5+1+3×(4-1)]:3=
=44-(5+1+3×3):3=
=44-(5+1+9):3=
=44-(6+9):3=
=44-15:3=
=44-5=
=39
k) 3:[(3-3:3+3+3:3):2]=
=3:[(3-1+3+1):2]=
=3:[(2+4):2]=
=3:(6:2)=
=3:3=
