Practicing Success
The area of the base of a cone is 616 sq. cm. Its height is 48 cm. Find its total surface area. |
2816 cm2 2861 cm2 2618 cm2 2681 cm2 |
2816 cm2 |
We know the base of a cone is circular Then, area of circle = πr2 = 616 $⇒r^2=\frac{616×7}{22}=196$ ⇒ r = 14 cm Also, total surface area of a cone = πr(r + l) Where ‘r’ is the radius of cone and ‘l’ is the slant height For a cone slant height = $l=\sqrt{r^2+h^2}$ $l=\sqrt{48^2+14^2}=\sqrt{2500}=50$ ∴ Total surface area = $\frac{22}{7}×14×(14+50)=2816cm^2$ |