This question was uploaded on 07/11/21 on social media accounts.
Solution:
We know that:
\[a^2+b^2+c^2+d^2=4r^2\]
Click here to read the proof of this identity.
\[Orange = \pi r^2\]
\[Green = a^2+b^2+c^2+d^2=4r^2\]
\[\frac{Orange}{Green}=\frac{\pi r^2}{4r^2}=\frac\pi4\]
