
From the figure, it can be observed that the side of the square is 42 cm.
Area of square = (Side)2 = (42)2 = 1764 cm2
Area of each circle = π r2
= 22/7 x 7 x 7 = 154 cm2
Area of 9 circles = 9 x 154 = 1386 cm2
Area of the remaining portion of the handkerchief = 1764 − 1386 = 378 cm2