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प्रश्न
The curved surface area of a right circular cone is 12320 cm2. If the radius of its base is 56 cm, then find its height.
उत्तर
CSA (cone) = `pirl` = 12320
`22/7 xx 56 xx l` = 12320
`l = 70 cm`
`h = sqrt(70^2 - 56^2)` = 42 cm
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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.
