a =varsta tatalui
b=varsta mamei
c=varsta copil mic
d=varsta copil mare
a+b+c+d=94
a=7c
3d+c=b ⇒ 3(2c-2)+c=b (am inlocuit d cu d=2c-2)
d=2c-2
7c+3(2c-2)+c+c+2c-2=94
7c+6c-6+4c-2=94
17c=94+6+2
17c=102
c=102/17
c=6 ani are copilul mic
a=6x7=42 are tatal
d=2x6-2=10 are copilul mare
b=10x3+6=36 ani are mama