[tex]a+b+c=620 \\ 12dam=120m \\ b=a-120 =\ \textgreater \ a=b+120\\ b=2c=\ \textgreater \ c=b/2 \\ b+120+b+b/2=620amplificam \\ 2b/2+240/2+2b/2+b/2=1240/2 \\ 5b=1240-240 \\ b=1000:5 \\ b=200 m. in .al2lea .balot \\ a=200+120=320 m.in .primul.balot \\ c=200:2=100m.in .al3lea.balot[/tex]