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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)
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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