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प्रश्न
A wire is bent to form a square of side 22 cm. If the wire is rebent to form a circle, its radius is ______.
पर्याय
22 cm
14 cm
11 cm
7 cm
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उत्तर
A wire is bent to form a square of side 22 cm. If the wire is rebent to form a circle, its radius is 14 cm.
Explanation:
Given, side of a square = 22 cm
Perimeter of square and circumference of circle are equal, because the wire has same length.
According to the question,
Perimeter of square = Circumference of circle
⇒ 4 × (Side) = 2 × π × r
⇒ 4 × 22 = `2 xx 22/7 xx r` ...`[∵ π = 22/7]`
⇒ r = `(4 xx 22 xx 7)/(2 xx 22)`
⇒ r = 14 cm
Hence, the radius is 14 cm.
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