First, we need to compute the area of the inner circle
Area of a circle is computed as follows:
[tex]A=\frac{\pi\cdot D^2}{4}[/tex]Substituting with D = 12 ft:
[tex]\begin{gathered} A=\frac{\pi\cdot12^2}{4} \\ A\approx113.1ft^2 \end{gathered}[/tex]Next, we need to calculate the area of the outer circle (its diameter is 3 + 12 + 3 = 18 ft), as follows:
[tex]\begin{gathered} A=\frac{\pi\cdot18^2}{4} \\ A\approx254.5ft^2 \end{gathered}[/tex]Finally, the approximate area of the track is 254.5 ft² - 113.1 ft² = 141.4 ft²