"Băiatul lui cântărește cincizeci și șapte de kilograme."

Translation: His boy weighs fifty seven kilograms.

[MihailHancu]

"His boy weighs 57 kilograms" is correct. Also, "His boy weighs 50 7 kilograms" is an extremely unnatural answer and should be removed.

[teirdez]

I put 57 just now and failed

[Pehat]

"Her boy weighs fifty seven kilograms" is not accepted.

[Lng52-._]

Pehat: I think your translation would be: "Băiatul ei cântărește cincizeci și șapte de kilograme." (Her boy weighs fifty-seven kilograms.")

[Coriander18]

Why not kilogrammes too?