[tex]\bf 1\frac{1}{4}\implies \cfrac{5}{4}\quad therefore\quad 1\frac{1}{4}~:~8\implies \cfrac{5}{4}~:~8\implies \cfrac{\quad \frac{5}{4}\quad }{8}\implies \cfrac{5}{32}\\\\
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\stackrel{actual~width}{\cfrac{\quad \frac{5}{2}\quad }{W}=\cfrac{5}{32}}\implies \cfrac{5}{2W}=\cfrac{5}{32}\implies \cfrac{5\cdot 32}{2\cdot 5}=W\implies \boxed{16=W}[/tex]
[tex]\bf \stackrel{actual~length}{\cfrac{\quad \frac{25}{4}\quad }{L}=\cfrac{5}{32}}\implies \cfrac{25}{4L}=\cfrac{5}{32}\implies \cfrac{25\cdot 32}{4\cdot 5}=L\implies \boxed{40=L}
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\stackrel{\textit{area of the park}}{16\cdot 40\implies 640}\\\\
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[tex]\bf \stackrel{actual~diameter}{\cfrac{\quad \frac{5}{4}\quad }{d}=\cfrac{5}{32}}\implies \cfrac{5}{4d}=\cfrac{5}{32}\implies \cfrac{5\cdot 32}{4\cdot 5}=d
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8=d\implies 4=\stackrel{radius}{r}
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\stackrel{\textit{area of the pond}}{\pi r^2\implies \pi 4^2\implies 16\pi }\quad \approx \quad 50.24[/tex]
