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प्रश्न
A wire when bent in the form of a square encloses an area of 484 cm2. If the same wire is bent into the form of a circle, find the area of the circle.
उत्तर
Area of the square = 484 cm2
Side of the square = `sqrt 484` = 22 cm
Perimeter of the square = 4 x 22 = 88 cm
Perimeter of square = perimeter of circle
21 π r = 88
r = `88 xx 7/22 xx 1/2`
r = 14 cm
Radius of circle = 14 cm
Area of cirde = 11π r2
`= 22/7 xx 14 xx 14`
= 616 cm2
Hence, area of the circle = 616 cm2
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