P URGENT I've got a timer going on but really need your help to answer this thank you!!
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Given:
The radius of inner circle = 13 yd.
The width of the shaded region = 8 yd
To find the area of the shaded region.
Now,
The radius of the outer circle = 13+8 yd = 21 yd
Formula
The area of a circle of radius r unit is [tex]\pi r^{2}[/tex] sq unit.
[tex]A = A_{1}-A_{2}[/tex]
where, [tex]A[/tex] = The area of the shaded region
[tex]A_{1}[/tex] = Area of the outer region
[tex]A_{2}[/tex]= Area of the inner region
Now,
[tex]A_{1}[/tex][tex]=[/tex] [tex]\pi (21^{2})[/tex]
[tex]A_{1} = (3.14)(21)(21)[/tex]
[tex]A_{1}[/tex][tex]= 1384.74[/tex] sq yd
And,
[tex]A_{2}[/tex] [tex]=[/tex] [tex]\pi (13^{2})[/tex]
[tex]A_{2} = (3.14)(13)(13)[/tex]
[tex]A_{2}[/tex][tex]= 530.66[/tex] sq yd
Therefore,
[tex]A = 1384.74-530.66[/tex] sq yd
[tex]A = 854.08[/tex] sq yd
Hence,
The area of the shaded region 854.08 sq yd.