6.i- irina
t- teodor
a- andrei
i+t=559 (1)
t+a=600 (2)
i+a=531 (3)
daca adunam toate trei relatiile, obtinem
2i+2t+2a=1690
2(i+t+a)=1690
i+t+a=845
si acum inlocuim pe rand relatiile 1-3 in suma
559+a=845, a=286
i+600=845, i=245
t+531=845, t=314
verificare: 286+245+314=845
Raspuns: Andrei are 286 puncte, Irina are 245 si Teodor are 314 puncte.
