Question

Find the surface area of a sphere with a diameter of 40 inches. Leave your answer in terms of pi.(1 point)
The surface area is in.2

Answer 1

To find the surface area of a sphere, you can use the formula:

\[
\text{Surface Area} = 4\pi r^2
\]

where \( r \) is the radius of the sphere.

Given that the diameter of the sphere is 40 inches, the radius \( r \) is half of the diameter:

\[
r = \frac{40}{2} = 20 \text{ inches}
\]

Now, substitute the radius into the surface area formula:

\[
\text{Surface Area} = 4\pi (20)^2
\]

Calculating \( (20)^2 \):

\[
(20)^2 = 400
\]

Now substitute back into the surface area formula:

\[
\text{Surface Area} = 4\pi \times 400 = 1600\pi
\]

Therefore, the surface area of the sphere is:

\[
\text{Surface Area} = 1600\pi \text{ in}^2
\]

So the final answer is:

\[
\text{Surface Area} = 1600\pi \text{ in}^2
\]