If $T$ is the total number of students, and $X$ is the total number of qualified students,

Qualification rate of girls $ =\frac{ 0.6X}{0.35T}$

Qualification rate of boys $= \frac{0.4X}{0.65T}$

The first one is clearly the winner here and it is independent of both $T$ (total number of candidates) and $X$ (total number of qualified candidates).

Qualification rate of girls $ =\frac{ 0.6X}{0.35T}$

Qualification rate of boys $= \frac{0.4X}{0.65T}$

The first one is clearly the winner here and it is independent of both $T$ (total number of candidates) and $X$ (total number of qualified candidates).