Question

What is the diameter of a circle that has an area of 452.16 mm 2?

Answer 1

Formula for Area of a circle = \(A = \pi \cdot D\) or \(A=\pi r^2\)

Given \(A= 452.16 \ mm^2\) plug A into the formula to solve for D \[\large 452.16= \pi D\]\[\large D = \dfrac{452.16}{\pi}\]

Answer 2

144

Answer 3

Not exactly :\ \[\large \cfrac{452.16}{\pi}\]\[\cfrac{228700}{1589}\] and reducing that you'll find your answer :)

Answer 4

\[A_\text{circle}=\pi r^2=\pi (D/2)^2=\pi D^2/4\]