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प्रश्न
A copper wire when bent in the form of a square encloses an area of 484 cm2. The same wire is not bent in the form of a circle. Find the area enclosed by the circle.
उत्तर
Area of the circle = 484 cm2
Area of the square = Side2
⇒ 484 = Side2
⇒ 222 = Side2
⇒ Side = 22 cm
Perimeter of the square = 4 × Side
Perimeter of the square = 4 × 22
= 88 cm
Length of the wire = 88 cm
Circumference of the circle = Length of the wire = 88 cm
Now, let the radius of the circle be r cm.
Thus, we have:
2πr = 88
`⇒ 2xx22/7xx"r"=88`
⇒ r = 14
Area of the circle = πr2
`=22/7xx14xx14`
= 616 cm2
Thus, the area enclosed by the circle is 616 cm2.
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