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Find the volume of a right circular cone with :
(i) radius 6 cm, height 7 cm.
(ii) radius 3.5 cm, height 12 cm
(iii) height 21 cm and slant height 28 cm.
i) we have,
Radius of cone = 6 cm
Height of cone = 7 cm
So, volume of cone = πr2h = 1/3 × 22/7 ×36×7 = 264 cm3
ii) we have,
radius = 3.5 cm
height = 12 cm
volume of cone = 1/3×22/7×3.5×3.5×12 = 154 cm3
iii) we have,
height = 21 cm
slant height = 28 cm
radius r = √(282-212) = √49×7 = 7√7 cm
volume of cone = 1/3×22/7×7√7×7√7×21 = 7546 cm3