Let ‘a’ be the side of the square in the picture.
Area of the square = a2
i. If the four sectors in the vertices are joined together, a circle is formed because the radius of each sector is a/2.
Area of the shaded part = Area of the square – area of the circle.
ii. In the second picture diameter of the circle = a Radius = a/2
Area of the shaded part = Area of the square – area of the circle.
i.e., Areas of the shaded portions are equal.