On a square handkerchief, nine circular designs each of radius 7 cm are made (see Fig. 12.29). Find the area of the remaining portion of the handkerchief.


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 = πr2


= * (7)2


= 154 cm2


Area of 9 circles = 9 × 154


= 1386 cm2


Area of the remaining portion of the handkerchief = 1764 - 1386


= 378 cm2


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