Q3 of 35 Page 311

Grandmother of Rekha was made a circular table cover of which area 5544 sq.cm. She wants to paste coloring tape surrounding this circular cover of the table, let us see by calculating how long coloring tape she will buy.

Given, Area of circular table cloth = 5544cm2


Since the coloring tape would be placed on the edge of the table cloth so to calculate the length of coloring tape required, we will calculate the perimeter of table cloth.


Now, area of a circle = πr2, where r is the radius of the circle


⇒ 5544 = πr2


⇒ (∵ π = )


⇒ 1764 = r2


⇒ r =


Perimeter = 2πr, where r is the radius of the circle


⇒ Perimeter


= 264 cm


Therefore, the length of coloring tape required is 264 cm


More from this chapter

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1

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