1000*a+100*b+10*c+2000+100*a+10*b+c+1000+100*a+10*b+c=4476
1200*a+120*b+12*c+3000=4476
1200*a+120*b+12*c=1476 |:12
100*a+10*b+c=123
Analiza:
100*a are ultima cifra 0
10*b are ultima cifra 0
=> c =3
100*a+10*b+3=123
100*a+10*b=120
Observam ca a<2 =>a=1 =>
100+10*b=120
10*b=20 => b=2
abc =123
verificare: 1230+2123+1123=4476 -ok!