a) 1/18+1/9+1/6
amplificam fiecare fractie pentru a ajunge la numitor comun (a doua fractie cu 2, iar a 3-a cu 3)
1/18+2/18+3/18= 6/18= 1/3
b) 7/36-1/18+3/4=
=7/36-2/36+27/36=
=32/36= 8/9
c) 37/18-3/4-5/6=
=74/36-27/36-30/36=
=17/36
d) 11/18-4/9+5/6-1/3=
=11/18-8/18+15/18-6/18=
=12/18= 2/3
