Question

I need to know the famous mathematical problems featuring pi

Answer 1

Here is all I know.

1. A circle of radius 3cm is dissected into 12 sectors of  each. Only one of them is bisected. And when they are all arranged together, they form a rectangle. What is the length of this rectangle?

Answer: We have arranged them to form a rectangle, so the height will be the radius, we know that. Now let's find the area of the circle.
=28.274. 
This is also the are of the rectangle. We know that area of a rectangle is
So let's simplify out.





Let's reverse that last equation.



9.424 is pretty much the same as .

So we can conclude the length is