[tex]\bf \textit{Annie travelled 5 times the hours of Brian}\\
\textit{the hours of both sum up to \underline{20}}
\\\\\\
\begin{cases}
b=\textit{hours Brian travelled}\\
a=\textit{hours Annie travelled}\\
----------\\
\boxed{a}=5b\\
a+b=\underline{20}
\end{cases}
\\\\\\
\boxed{5b}+b=20\implies 6b=20\implies b=\cfrac{20}{5}\implies b=4[/tex]
how many hours Annie travelled? Well, a = 5b.
