4)35-17=18 diferenta dintre feb si martie 893-35-18=840 turisti s-ar fi cazat in mod egal in cele 3 luni ;840:3=280(luna ianuarie);280+35=315(luna februarie);315-17=298(luna martie) ;280+315+298 = 893 (turisti cazati in primele 3 luni)
5) la I
d=87+19=106
c=d-36=106-36=70
b=c*3=70*3=210
a=b:2=210:2=105
la a II a
d=294:6=49
c=d*4=49*4=196
b=c-29=194-29=167
a=b+304=167+304=471
la a III a
e=19*6=114
d=e:6=114:6=19
c=d+13=19+13=32
b=c*9=32*9=288
a=300-b=300-288=12
la a IV a
e=5*10=50
d=250+50=300
c=d:10=300:10=30
b=c*3=30*3=90
a=b-90=90-90=0
6)987-102=885
885-8=877
877-4=873
873-2=871
