A math lab of 12 students has 9 girls . Next semester math lab enrolls 36 students, the expected numbers of girls can be calculated as follows
[tex]\begin{gathered} 12\text{ student = 9 girls} \\ 36\text{ students = ?} \\ \text{cross multiply} \\ \text{expected number of girls = }\frac{36\times9}{12} \\ \text{expected number of girls = }\frac{324}{12} \\ \text{expected number of girls = }27 \end{gathered}[/tex]