Răspuns:
intrebarea problemei: cate kg de carbuni transporta fiecare tren?
a+b+c=7296
a+b=3517
3517+c=7296=>c=7296-3517=>c=3779 kg carbuni transporta al3lea tren
b+c=5823
a+5823=7296=>a=7296-5823=>a=1473 kg carbuni transporta primul tren
a+b=3517=>1473+b=3517=>b=3517-1473=>b=2044 kg carbuni transporta al2lea tren
verificare :
a+b+c=1473+2044+3779=7296 kg
