since 2 hours is 120 minutes, then
[tex]\bf \begin{array}{ccll}
\stackrel{download}{minutes}&\stackrel{show}{minutes}\\
\text{\textemdash\textemdash\textemdash}&\text{\textemdash\textemdash\textemdash}\\
13&39\\
x&120
\end{array}\implies \cfrac{13}{x}=\cfrac{39}{120}\implies \cfrac{13\cdot 120}{39}=x[/tex]
