From the equation:
[tex]\frac{a}{5}=\frac{18}{30}[/tex]We can solve for a by multiplying both sides by 5, like this:
[tex]\begin{gathered} \frac{a}{5}=\frac{18}{30} \\ 5\times\frac{a}{5}=\frac{18}{30}\times5 \\ a\times\frac{5}{5}=\frac{18}{6} \\ a\times1=3 \\ a=3 \end{gathered}[/tex]Then, a equals 3
