Answer: Perimeter = 6π ≈ 18.84
Area = 15π ≈ 47.10
Explanation:
This is a composite of a big semicircle with diameter of 10 --> radius (r) = 5
plus a medium semicircle with diameter of 6 --> r = 3
minus a small semicircle with diameter of 4 --> r = 2
Perimeter of a semicircle =
![(1)/(2)(2\pi r)=\pi r](https://img.qammunity.org/2021/formulas/mathematics/high-school/2y0eyyhh5r2fe05149p004ez8jkt9sp30t.png)
![P_(big)=\pi (5)\quad =5\pi\\P_(medium)=\pi (3)\quad =3\pi\\P_(small)=\pi (2)\quad =2\pi\\P_(composite) =5\pi+3\pi -2\pi\\.\qquad \qquad =\large\boxed{6\pi}](https://img.qammunity.org/2021/formulas/mathematics/high-school/ckque6cn6m192vql0cofhoo983tb6ui9qf.png)
Area of a semicircle =
![(1)/(2)(\pi r^2)](https://img.qammunity.org/2021/formulas/mathematics/high-school/yqe9d6wm52t4n48dqcp8u6vt8ojdwm53ot.png)
![A_(big)=(1)/(2)\pi (5)^2\quad =12.5\pi\\\\A_(medium)=(1)/(2)\pi (3)^2\quad =4.5\pi\\\\A_(small)=(1)/(2)\pi (2)^2\quad =2\pi\\\\A_(composite) =12.5\pi+4.5\pi -2\pi\\\\.\qquad \qquad =\large\boxed{15\pi}](https://img.qammunity.org/2021/formulas/mathematics/high-school/kbf6err2gm1iybhquboc7z6o0l9p6pc5ur.png)