Respuesta :

To calculate the area of the doughnut, we need to calculate the area of the larger circle and substract the area of the smaller circle.

The area of a circle can be calculated using its radius:

[tex]A=\pi r^2[/tex]

The diameter of the larger circle is 6cm which meand that its radius is half as large, so the radius is 3 cm and the area of the larger circle is:

[tex]A_L=\pi3^2=9\pi[/tex]

Area of 9π cm².

The smaller one have a diameter of 2 cm, so its radius is half as large, radius of 1 cm.

So, the area of the smaller circle is:

[tex]A_S=\pi1^2=\pi[/tex]

Area of π cm².

The total shaded area is, then, the area of the larger minus the area of the smaller.

So, the shaded area is:

[tex]\begin{gathered} A=A_L-A_S \\ A=(9\pi-\pi)cm^2 \\ A=8\pi cm^2 \\ A\approx(9\cdot3)cm^2 \\ A\approx27cm^2 \end{gathered}[/tex]