Let's first find the area of sheet 1 and the area of the largest circle in it
Let's say the side of each parallelogram is P and two opposite angles of 60-degree measures are given
In parallelogram consecutive angles are complementary, based on the other two angles will be 120 degrees each.
Based on the figure attached of a parallelogram, we can find its height of it based on the Pythagoras theorem.
Triangle of 30:60:90 = 1:\(\sqrt{3}\):2, the height of the parallelogram would be \(\frac{\sqrt{3}P}{2}\)
So area of the parallelogram sheet 1 = base * height = P * \(\frac{\sqrt{3}P}{2}\) = \(\frac{\sqrt{3}P^2}{2}\)
Now, the Height of the parallelogram = Diameter of the largest inscribed circle = \(\frac{\sqrt{3}P}{2}\)
so area of that circle 1 = \(\frac{\pi*Diameter^2}{4}\) = \((\frac{\pi}{4})*(\frac{\sqrt{3}P}{2})^2\)
Now, Let's count the area of sheet 2 and the area of the circle inscribed in it
Let's length of the square sheet S
So area of the square sheet 2 = \(S^2\)
Height of the square = diameter of the largest circle inscribed in it = S
So the area of circle 2 = \(\frac{\pi*Diameter^2}{4}\) = \(\frac{\pi*S^2}{4}\)
Now the area of both circles is the same,
\((\frac{\pi}{4})*(\frac{\sqrt{3}P}{2})^2\) = \(\frac{\pi*S^2}{4}\)
\(\frac{3*P^2 }{4 }\) = \(S^2\)
\(\frac{P^2 }{ S^2 }\) = \(\frac{4}{3}\)Now, the ratio of the area of both sheets = \(\frac{Area of sheet 1 }{ Area of sheet 2}\)
= \(\frac{(\sqrt{3}P^2)}{2*(S^2)}\)
= \(\frac{\sqrt{3}}{2}\)*\(\frac{4}{3}\)
=
\(\frac{2}{\sqrt{3}}\)That the answer
(B)
Attachments

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