[tex]x-total\ number\ of\ seats\\x-52-occupied\ seats\\75\%=0.75\\100\%=1\\\\From\ proportion:\\\\x-52\ \ \ -\ \ \ 0.75\\x\ \ \ \ \ \ \ \ \ \ -\ \ \ 1\\\\x-52=0.75x\\x-0.75x=52\\0.25x=52\ \ \ \ |\cdot4\\x=208\\\\Total\ number\ of\ seats\ was\ 208.[/tex]