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.
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