UPSC CDS Math Area and Perimeter Questions

We have,
A square which is inscribed in a circle thus square vertices touch the circle
∴ Radius of circle =201mm
Thus, diagonal of the square = diameter of circle =2×201=402mm
We know that area of circle =πr2
=π×(201)2mm2
We know that area of square
‌‌=‌

1

2

×(2×201)2
So, the ratio of area of circle to
‌‌=‌

π×(201)2

2×(201)2

‌‌=‌

π

2

‌‌=‌

22

7×2

=‌

11

7