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The circumference of a circle is 31.4 cm. Find the radius and the area of the circle? (Take π = 3.14)

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प्रश्न

The circumference of a circle is 31.4 cm. Find the radius and the area of the circle? (Take π = 3.14)  

योग
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उत्तर

Let r be the radius of circle.

Circumference = 2πr = 31.4 cm

2 × 3.14 × r = 31.4

r = 5 cm

Area = 3.14 × 5 × 5

= 78.50 cm2

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अध्याय 9: Perimeter and Area - EXERCISE 9.2 [पृष्ठ १५९]

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एनसीईआरटी Mathematics [English] Class 7
अध्याय 9 Perimeter and Area
EXERCISE 9.2 | Q 12. | पृष्ठ १५९

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