we can use cross multiplication
[tex]\begin{gathered} 3\text{sail}\longrightarrow5\text{fan} \\ 54\text{sail}\longrightarrow\text{xfan} \end{gathered}[/tex]where x is the number of fan boats
[tex]\begin{gathered} x=\frac{54\times5}{3} \\ \\ x=90 \end{gathered}[/tex]the number of fan boats to 54 sailboats is 90