The circumference of a circle is 66 feet. What is the area? Use 22/7

circumference is pi*diameter and area is pi*(diameter/2)² so

area = pi*(circumference/2pi)²  or area = (circumference/2)²*1/pi

area = (66/2)²*7/22

$${\mathtt{area}} = {\frac{{\left({\frac{{\mathtt{66}}}{{\mathtt{2}}}}\right)}^{{\mathtt{2}}}{\mathtt{\,\times\,}}{\mathtt{7}}}{{\mathtt{22}}}} \Rightarrow {\mathtt{area}} = {\mathtt{346.5}}$$  

  area = 346.5ft²

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