Please help me I was on breaks and I don’t get this

Given
Answer
[tex]\begin{gathered} p=\frac{k}{q} \\ p=17,q=4 \\ 17=\frac{k}{4} \\ k=68 \\ \end{gathered}[/tex]Again put p=2
[tex]\begin{gathered} 2=\frac{k}{q} \\ 2=\frac{68}{q} \\ q=34 \end{gathered}[/tex]