Question

Curved surface area of a cone = Trl, where r is the

radius and I is the slant height.
surface area of a sphere = 42, where r is the
radius.
The shape below is made from a hemisphere and a
cone, each with a radius of 6 cm.
Work out the surface area of this shape in terms of .
16 cm
6 cm
Not drawn accurately

Answer 1

168π cm²

Explanation:

The total surface area is the sum of the areas of the parts: a hemisphere and a cone.

__

area formula

The area of a hemisphere is half the area of a sphere, so the total area is ...

total area = hemisphere area + cone area

= 2πr² +πrl

total area = πr(2r +l)

__

application

For the given dimensions, r = 6 cm, l = 16 cm, the total surface area is ...

total area = π(6 cm)(2(6 cm) +16 cm) = π(6)(28) cm²

total area = 168π cm²