The fact had already been known; when a so-called secret is known by two people, it's basically a semi-public secret.
Not to mention that more than two people knew about it.
At the time, Chen Yiwen was showing off in front of three girls.
Actually, if the class-division exam's questions were on par with the school's standard exam, it wouldn't have been a big issue.
Unfortunately, in the afternoon, Xu Dajiang obligingly chose one set out of the thirteen left by the already-departed Luo for the School of Mathematics' class-division paper.
As you can imagine, the mood of the freshmen post-exam was evident.
Therefore, an indignant young girl exposed all the facts she had heard from Chen Yiwen directly in the class group chat for the 23rd-grade freshmen.
It then spread rapidly through the School of Mathematics freshmen groups, group by group.