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प्रश्न
The perpendicular height of a cone is 12 cm and its slant height is 13 cm. Find the radius of the base of the cone.
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उत्तर
Let the radius of the base of the cone be r cm.
Height of the cone, h = 12 cm
The slant height of the cone, l = 13 cm
Now,
`"r"^2 +"h"^2 = "l"^2`
⇒ `"r"^2 + (12)^2 = (13)^2`
⇒ `"r"^2 + 144 = 169`
⇒ `"r"^2 = 169 - 144 = 25`
⇒ `"r" = sqrt(25) = 5 "cm"`
Thus, the radius of the base of the cone is 5 cm.
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