Question

The radio of girls to boys on Lisa's class is 5 to 4. How many girls are in her classroom if there is a total of 27 students?

Answer 1

in plain and short, we simply divide 27 by (5+4) and distribute accordingly.

`\bf \cfrac{girls}{boys}\qquad \cfrac{5}{4}~\hspace{7em}\cfrac{5\cdot (27)/(5+4)}{4\cdot (27)/(5+4)}\implies \cfrac{5\cdot 3}{4\cdot 3}\implies \cfrac{\stackrel{\stackrel{girls}{\downarrow }}{15}}{12}`