Let the number of girls $$=x$$
$$Girls:Boys \ =9 : 11$$
No. of boys $$=2035$$
$$x:2035=9:11$$
$$\Rightarrow \dfrac{x}{2035} = \dfrac{9}
{11} \Rightarrow 11 \times x=9 \times 2035$$
$$\Rightarrow x=\dfrac{9 \times 2035}{11} =
9 \times 185 \Rightarrow x=1665$$
No, of girls $$=1665$$
Total student in school $$=$$ no. of boys $$+$$ No, of girls
$$2035+1665=3700$$