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प्रश्न
A wire, when bent in the form of a square; encloses an area of 196 cm2. If the same wire is bent to form a circle; find the area of the circle.
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उत्तर
Area of Square = 196 cm2
Side of Square = `sqrt("Area")` = `sqrt(196)` = 14 cm
Perimeter of Square = 4 x 14 cm
i.e. length of wire = 56 cm
Circumference of circle = 56 cm
2πr = 56
`2 xx 22/7 xx r = 56`
`r = (56 xx 7)/(2 xx 22)`
`r = 98/11` cm
`therefore "Area of circle enclosed" = pir^2`
= `22/7 xx 98/11 xx 98/11`
= `2744/11`
= 249.45 cm2
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