THREE young men found guilty of raping a 15-year-old prostitute were freed yesterday when the Court of Appeal ruled that their convictions were unsafe and unsatisfactory. The Chief Justice, Sir Ti Liang Yang, supported the convictions, but Vice-President Mr Justice Macdougall and Mr Justice Barnett opposed. They said that in the course of his summing-up, the trial judge expressed an opinion based on hearsay evidence, which was inadmissible. They quashed the convictions and set aside the nine-year jail term imposed on Yuen King-lok and the eight-year terms on Lee Chi-wai and Leung Yiu-wa. Mr Yuen, 19, Mr Lee, 22, and Mr Leung, 24, were found guilty of rape in June last year by Deputy Judge Sharwood. The Crown alleged Mr Yuen pimped for the girl. On December 28, 1990, she was taken to a flat where she was said to have been forced by Mr Yuen to have sex with seven men, including Mr Lee and Mr Leung.