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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 = π*r*^{2}*h* = 1/3 × 22/7 ×36×7 = 264 cm^{3}

ii) we have,

radius = 3.5 cm

height = 12 cm

volume of cone = 1/3×22/7×3.5×3.5×12 = 154 cm^{3}

iii) we have,

height = 21 cm

slant height = 28 cm

radius r = √(28^{2}-21^{2}) = √49×7 = 7√7 cm

volume of cone = 1/3×22/7×7√7×7√7×21 = 7546 cm^{3}

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