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प्रश्न
Find the surface area of a sphere of radius 7 cm.
Solution :
The surface area of the sphere = 4πr2
= `4 xx 22/7 xx square^2`
= `4 xx 22/7 xx square`
= `square xx 7`
∴ The surface area of the sphere = `square` sq.cm.
उत्तर
The surface area of the sphere = 4πr2
= `4 xx 22/7 xx bbunderline7^2`
= `4 xx 22/7 xx underlinebb49`
= 88 × 7
∴ The surface area of the sphere = 616 sq.cm.
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