हिंदी

Priyanka took a wire and bent it to form a circle of radius 14 cm. Then she bent it into a rectangle with one side 24 cm long. What is the length of the wire? Which figure encloses more area

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प्रश्न

Priyanka took a wire and bent it to form a circle of radius 14 cm. Then she bent it into a rectangle with one side 24 cm long. What is the length of the wire? Which figure encloses more area, the circle or the rectangle?

योग
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उत्तर

Given that, radius of circle (r) = 14 cm and length of rectangle (l) = 24 cm

∴ Length of the wire = Circumference of the circle

= 2πr

= `2 xx 22/7 xx 14`

= 88 cm

Let b be the width of rectangle.

Since, the wire is rebent in the form of rectangle.

∴ Perimeter of rectangle = Circumference of circle

⇒ 2(24 + b) = 88

⇒ 24 + b = 44

⇒ b = 44 – 24

⇒ b = 20 cm

Area of circle = πr2

= `22/7 xx (14)^2`

= 616 cm2

∵ Area of rectangle = l × b

= 24 × 20

= 480 cm2

Hence, the circle encloses more area than rectangle.

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  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 9: Perimeter and Area - Exercise [पृष्ठ २९०]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar Class 7
अध्याय 9 Perimeter and Area
Exercise | Q 108. | पृष्ठ २९०

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