The surface area of the frustum cone is given its base radius, R = 12 m and top radius, r = 9 m. The height of the cone is 4 m. Find the slant height of the cone.

Q. Find the total surface area of a cone, if its slant height is

9 m

and the radius of its base is

12 m

Join BYJU'S Learning Program

The slant height of a cone is 40 m, the radius of the base is 12 m. Find the curved surface area of a cone.

The correct option is C 1507.2 m2We know, curved surface area of the cone=πrswhere, π=3.14.Given, radius r=12 mand slant height s=40 m.∴ Curved surface area=3.14×12×40=1507.2m2.Hence, option C is correct.

The slant height of a cone is $40$ m, the radius of the base is $12$ m. Find the curved surface area of a cone.

The correct option is C $1507.2 m^{2}$
We know, curved surface area of the cone $= π r s$
where, $π = 3.14$ .

Given, radius $r = 12 m$
and slant height $s = 40 m$ .

$∴$ Curved surface area $= 3.14 \times 12 \times 40 = 1507.2 m^{2}$ .

Hence, option $C$ is correct.