Question

Surface area of cones practice
What is the surface area in square meters of a cone with a slant height of 8 meters and a radius of 5 meters use 3.14 for pi and round the nearest tenth if necessary

Answer 1

The surface area \(A\) of a cone can be calculated using the formula:

\[
A = \pi r (r + l)
\]

where \(r\) is the radius, \(l\) is the slant height, and \(\pi\) is approximately 3.14.

Given:
- Radius \(r = 5\) meters
- Slant height \(l = 8\) meters

Now, substitute the values into the formula:

\[
A = 3.14 \times 5 \times (5 + 8)
\]

First, calculate \(5 + 8\):

\[
5 + 8 = 13
\]

Now substitute this value back into the surface area formula:

\[
A = 3.14 \times 5 \times 13
\]

Calculating \(5 \times 13\):

\[
5 \times 13 = 65
\]

Now, calculate \(A\):

\[
A = 3.14 \times 65
\]

Calculating \(3.14 \times 65\):

\[
3.14 \times 65 = 204.1
\]

Thus, the surface area of the cone is approximately

\[
\boxed{204.1} \text{ square meters.}
\]