[tex]Perimeter \ of \ a \ fence \ a \ yard : \\ \\P=2w + 2l \\length : l =30\ m \\width : \ w =18 \ m\\\\ P=2\cdot 18+2\cdot 30=36+60=96 \ m \\\\posts \ 2 \ m \\\\96 \ m : 2 \ m =48 \ posts \\\\Answer : \ 48 \ post \ are \ needed \ to \ fence \ a \ yard [/tex]
