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A wire is bent to form a square of side 22 cm. If the wire is rebent to form a circle, its radius is ______. - Mathematics

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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 ______.

विकल्प

  • 22 cm

  • 14 cm

  • 11 cm

  • 7 cm

MCQ
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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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अध्याय 9: Perimeter and Area - Exercise [पृष्ठ २६८]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 7
अध्याय 9 Perimeter and Area
Exercise | Q 4. | पृष्ठ २६८

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