1)a-b=517
a=2b
2b-b=517
b=517
a=1034
2)T=2M
I=4M
T+M+I=518
2M+M+4M=518
7M=518
M=74
T=74 x 2=148
I=74 x 4=296
M=Manuela
I=Ingrid
T=Tudor
3)a+b=1493
a-b=83
a=b+83
b+83+b=1493
2b+83=1493
2b=1410
b=705
a=705+83=788
4)a+b+c=189
b=2a
c=4a
a+2a+4a=189
7a=189
a=27
b=27 x 2=54
c=27 x 4=108
5)a+b+c+d=1142
a,b,c,d-nr consecutive
b=a+1
c=a+2
d=a+3
a+a+1+a+2+a+3=1142
4a+6=1142
4a=1142-6=1136
a=284
b=285
c=286
d=287
6)a+b=1633
b=a+1
a+a+1=1633
2a=1632
a=816
b=817
7)a+b=1244
a,b-nr impare
b=a+2
a+a+2=1244
2a+2=1244
2a=1242
a=621
b=623
8)x+y=980
x=y+58
y+58+y=980
2y=980-58=922
y=461
x=461+58=519
9)a+b+c=513
a,b,c-nr impare
b=a+2
c=a+4
a+a+2+a+4=513
3a+6=513
3a=507
a=169
b=171
c=173
10)tMiruna+tMihaela=51 timbre
tMiruna=2tMihaela
2tMihaela+tMihaela=15
3tMihaela=15
tMihaela=5
tMiruna=5 x 2=10
t-timbre