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प्रश्न
In a right circular cone, if the perpendicular height is 12 cm and the radius is 5 cm, then find its slant height.
उत्तर
Heights (h) = 12 cm
Radius (r) = 5 cm
∴ Slant height (l) = `sqrt (h^2 + r^2)`
= `sqrt(12^2 + 5^2)`
= `sqrt(144 + 25)`
= `sqrt(169)`
= 13 cm
∴ l = 13 cm
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