Dau coroana și ma abonez!

a)3/2-1/2:3/4=
3/2-1/2×4/3=
3/2-2/3=
5/6
b)3/2:{2/9•[5/2-(1/5+1/2)•5/2]-1/7}=
3/2:[2/9•(5/2-7/10•5/2)-1/7]=
3/2:[2/9•(5/2-7/4)-1/7]=
3/2:(2/9•3/4-1/7)=
3/2:(1/6-1/7)=
3/2:1/42=
3/2×42=
3×21=
63