A toy is in the form of a cone mounted on a hemisphere
Question:

A toy is in the form of a cone mounted on a hemisphere with the same radius. The diameter of the base of the conical portion is 6 cm and its height is 4 cm. Determine the surface area of the toy. (Use π = 3.14)

Solution:

Radius of hemisphere and the cone are the same.
So, r = 3 cm
Surface area of the cone

$=\pi r l$

$=3.14 \times 3 \times \sqrt{3^{2}+4^{2}}$

$=47.1 \mathrm{~cm}^{2}$

Surface area of the hemisphere

$=2 \pi r^{2}$

$=2 \times 3.14 \times 9$

$=56.52 \mathrm{~cm}^{2}$

Total surface area of the toy = Surface area of the cone + surface area of the hemisphere

=47.1 + 56.52 cm2

=103.62 cm2