First, draw a diagram to visualize the situation:
The area of the region covered with small rocks can be found by subtracting the area of the circle from the area of the square.
The area A_s of a square with side L is given by:
[tex]A_s=L^2[/tex]And the area A_c of a circle with radius r is given by:
[tex]A_c=\pi r^2[/tex]Replace r=4ft and L=10ft into the equations to find the area of the circle and the square:
[tex]\begin{gathered} A_s=(10ft)^2=100ft^2 \\ A_c=\pi(4ft)^2=16\pi ft^2\approx50.265ft^2 \end{gathered}[/tex]Finally, subtract the area of the circle from the area of the square to find the area of the region covered with rocks:
[tex]A=A_s-A_c=100ft^2-16\pi ft^2\approx49.7ft^2[/tex]Therefore, the area of the region covered with rocks is exactly 100-16π square feet, which is approximately equal to 49.7 square feet.
