Question

A metallic cylinder of radius 8 cm and height 2 cm is melted and converted into a right circular cone of height 6 cm. The radius of the base of this cone is

Options

• 4 cm

• 5 cm

• 6 cm

• 8 cm

Answer 1

8 cm

Radius of the cylinder = 8 cm

Height of the cylinder = 2 cm

Height of the cone = 6 cm

Volume of the cylinder  = Volume of the cone

Therefore,

`pixx8xx8xx2xx=1/3pixx"r"^2xx6`

`=>128 = "r"^2xx2`

`=> "r"^2 = 128/2`

`=>  "r"^2 = 128/2 `

`=> "r"^2 = 64`

`=> "r" = 8  "cm"`

Hence, the radius of the base of the cone is 8 cm.