Find the total surface area of a cone whose radius is $12$ m and the slant height is $23$ m.
$420 π {mm}^{2}$
$420 π {cm}^{2}$
$420 π m^{2}$
$420 π m$

Question

Find the total surface area of a cone whose radius is $12$ m and the slant height is $23$ m.
$420 π {mm}^{2}$
$420 π {cm}^{2}$
$420 π m^{2}$
$420 π m$

Toppr Admin · Accepted Answer

Total surface area of cone is-xA0-S-x3C0-r-r-l-Here- radius is r-12 m and slant height is l-23 m-Thus-S-x3C0-r-r-l-x3C0-xD7-12-12-23-12-x3C0-xD7-35-420-x3C0- m2Hence- the total surface area-xA0-of the cone is-xA0-420-x3C0-xA0-m2-Therefore- option C is correct-

Find the total surface area of a cone whose radius is 12 m and the slant height is 23 m.420π mm 2420π cm 2420π m 2420π m

Total surface area of cone is S=πr(r+l).Here, radius is r=12 m and slant height is l=23 m.Thus,S=πr(r+l)=π×12(12+23)=12π×35=420π m2Hence, the total surface area of the cone is 420πm2.Therefore, option C is correct.

Find the total surface area of a cone whose radius is $12$ m and the slant height is $23$ m.
$420 π {mm}^{2}$
$420 π {cm}^{2}$
$420 π m^{2}$
$420 π m$

Total surface area of cone is $S = π r (r + l)$ .

Here, radius is $r = 12$ m and slant height is $l = 23$ m.

Thus,

$S = π r (r + l) = π \times 12 (12 + 23) = 12 π \times 35 = 420 π$ m $^{2}$

Hence, the total surface area of the cone is $420 π$ m $^{2}$ .

Therefore, option $C$ is correct.