Question

Calculating an approximation of pi using a square inside a circle

Answer 1

I need to find a close approximation of pi using a square inside a circle

Answer 2

well you could say
\[\text{ small square area }<\text{ circle area } < \text{ big square area }\]


so you have:
\[r^2 <\text{ circle area} <R^2 \\ \text{ hmmm... circle area} \approx \frac{R^2+r^2}{2}\]