We know that the total is 40 students, and 24 of them are girls, then the fraction that represents it is
[tex]\frac{24}{40}[/tex]But we must simplify the fraction, let's divide the denominator and numerator by 4
[tex]\frac{24}{40}=\frac{6}{10}[/tex]Now we can do it again by 2
[tex]\frac{24}{40}=\frac{6}{10}=\frac{3}{5}[/tex]Therefore the correct answer is the letter B.
[tex]\frac{3}{5}[/tex]