Q14 of 47 Page 1

A wire when bent in the form of an equilateral triangle encloses an area of 121√3 cm2. If the wire is bent in the form of a circle, find the area enclosed by the circle (use ).

Area of an Equilateral Triangle =

where a represents the length of sides


Given Area of Equilateral Triangle 121√3 cm2


⇒


⇒ a2 = 121 × 4


⇒ a = 22 cm


Perimeter of the triangle = 22 × 3 = 66 cm.


Since the full wire is made into a circle


Circumference of the circle = 66 cm.


Let Radius of the circle be r



⇒


⇒ r = 10.5 cm



Area of circle =


Answer: Area of Circle = 346.5 cm2


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