A well has to be dug out 20 m deep and its radius is 3.5 m. Find the cost of plastering the inner curved surface at Rs 5 per square meter.

A cone of the height 54 cm and radius of the base of 4 cm is made up of clay. Aditya reshapes it in the form of a sphere. The radius of the sphere will be

A metallic sphere of radius 6 cm is melted and recast into a cone of radius 4 cm. Find the height of the cone.

Consider the following statements:

I. If the height of a cylinder is doubled, the area of the curved surface is doubled.

II. If the radius of a hemispherical solid is doubled, its total surface area becomes fourfold.

Which of the above statement(s) is / are true:

A drainage tile is a cylindrical shell 21cm long. The inside and outside diameters are 4.5 cm and 5.1 cm, respectively.

What is the volume of clay required for making a tile?

If each side of a cube is reduced by 50%, the surface area will reduced by.

If the ratio of the radii of the sphere and hemisphere is √3:2, then determine the ratio of their total surface area?