Surface Areas a...

If n coins each of diameter $$1.5\ cm$$ and thickness $$0.2\ cm$$ are melted and a right circular cylinder of height $$10\ cm$$ and diameter $$4.5\ cm$$ is made, then $$n =$$

A well with 14 m diameter is dug 8 m deep. The earth taken out of it has been evenly spread all around it to a width of 21 m to form an embankment. Find the height of the embankment.

A frustum of a right circular cone is of height $$16$$ cm with radii of its ends as $$8$$ cm and $$20$$ cm has lateral surface area equal to

A solid iron rectangular block of dimensions 4.4 m, 2.6 m and 1 m is cast into a hollow cylindrical pipe of internal radius 30 cm and thickness 5 cm. Find the length of the pipe.

Diameter of the base of a cone is $$10.5cm$$ and its slant height is $$10cm$$. Find its curved surface area.

A solid wooden toy is in the shape of a right circular cone mounted on a hemisphere with same radius. If the radius of the hemisphere is 4.2 cm and the total height of the toy is 10.2 cm, find the volume of the wooden toy. (Take $$\pi$$ = 22/7)

A solid is in the form of a cone of vertical height $$9 cm$$ mounted on the top base of a right circular cylinder of height $$40 cm$$. The radius of the base of the cone and that of the cylinder are both equal to $$7 cm$$. Find the weight of the solid if $$1\, cm^{3}$$ of the solid weighs $$4 gm.$$

A frustum of a right circular cone is of height $$16$$ cm with radii of its ends as $$8$$ cm and $$20$$ cm. What is the volume of the frustum?

A tent is in the form of a cylinder of diameter $$8\ \mathrm{ m} $$ and height $$ \ \mathrm{2 m} $$, and surmounted by a cone of equal base and height $$ 3 \ \mathrm{m} $$. The canvas used for making the tent is equal to:

Curved surface area of a cone is $$308{cm}^{2}$$ and its slant height is $$14cm$$. Find total surface area of the cone.