Formula: 1 Mark
Application: 2 Marks
Answer: 1 Mark
Given that
A square of side '$x$' meters is bent into a circle.
The perimeter of the square = $4\times x$
The circle will have the same perimeter as that of the square = $4\times x$ metres
Circle will be having a radius(r) = $\frac{4x}{2\pi }$
Area of the Circle so formed 
= $\pi \times \left(\frac{4x}{2\pi }\right)\frac{4x}{2\pi }{m}^2=\frac{4x^2}{\pi }$
The circle which is half cut has a circumference of 2$x$.
Square bent from half circle has the circumference of 2$x$ meters.
Side of the square = $\frac{2x}{4}$
 Area of the square = $\frac{x^2}{4}$
Putting x = 2
We get the area of the circle
= $\frac{4}{\pi }\times 2^2$  = 5.09 $m^2$
The area of the square = $\frac{4}{4}$ = 1$m^2$
The difference between the area of the circle and the area of the square
= 5.09 - 1 = 4.09 $m^2$