How old was Ji Qin when he first met you?

In the Global College Entrance Examination, Ji Qin and You Xun were both 22 when they first met, and Ji Qin was two years older than You Xun. When they first met, Ji Qin entered the secret investigation system as a candidate. At this time, You Huo was the first invigilator A selected by the system, and Ji Qin came in with the task of destroying the system.