a) 0 (totul e înmulțit cu 0)
b)50+1-50=1
c) (23+529)÷23=552÷23=24
d)120÷6-180÷9+2-2=20-20+2-2=0
e)255÷5-(20-0)÷2=51-10=41
f)30+5×{4+5×[40+8× (40-36)]}=30+5×[4+5×(40+8×4)]=30+5×(4+5×72)=30+5×364=30+1820=1850
g) (780+150)÷30×25-774=930÷30×25-774=31×25-774=775-774=1