A larger cylinder-shaped cushion has a height of 1 foot and a diameter of 4 feet. How many square feet of fabric will be needed to reupholster the entire cushion? Use 3.14 for pi.(1 point)

Responses

125.6 square feet
125.6 square feet
25.12 square feet
25.12 square feet
37.68 square feet
37.68 square feet
12.56 square feet

1 answer

To calculate the amount of fabric needed to reupholster the entire cylinder-shaped cushion, you need to find the surface area of the cylinder. The formula for the surface area \( A \) of a cylinder is:

\[ A = 2\pi r^2 + 2\pi rh \]

Where:

  • \( r \) is the radius of the base of the cylinder.
  • \( h \) is the height of the cylinder.

Given:

  • Diameter of the cushion = 4 feet, therefore the radius \( r = \frac{4}{2} = 2 \) feet.
  • Height \( h = 1 \) foot.
  • Using \( \pi \approx 3.14 \).

Now, we can calculate the surface area.

  1. Calculate \( 2\pi r^2 \): \[ 2\pi r^2 = 2 \times 3.14 \times (2)^2 = 2 \times 3.14 \times 4 = 25.12 \text{ square feet} \]

  2. Calculate \( 2\pi rh \): \[ 2\pi rh = 2 \times 3.14 \times 2 \times 1 = 2 \times 3.14 \times 2 = 12.56 \text{ square feet} \]

  3. Add the two areas together to get the total surface area: \[ A = 25.12 + 12.56 = 37.68 \text{ square feet} \]

Thus, the total fabric needed to reupholster the cushion is 37.68 square feet.

So, the correct response is:

37.68 square feet.