A cone shows a base diameter of 25 centimeters, perpendicular height from the base to the top vertex at 90 degrees, and 22 centimeters as the hypotenuse or the side of the cone.

What is the surface area of the cone? Use 3.14 for pi.

(1 point)
Responses

863.5 square centimeters
863.5 square centimeters

3,689.5 square centimeters
3,689.5 square centimeters

2,383.26 square centimeters
2,383.26 square centimeters

1,354.125 square centimeters

1 answer

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

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

where:

  • \( r \) is the radius of the base,
  • \( l \) is the slant height of the cone.

Given:

  • The base diameter of the cone is 25 centimeters, so the radius \( r \) is: \[ r = \frac{25}{2} = 12.5 \text{ cm} \]

  • The slant height \( l \) is given as 22 centimeters.

Now, substituting the values into the surface area formula:

  1. Calculate the area of the base: \[ \pi r^2 = 3.14 \times (12.5)^2 = 3.14 \times 156.25 = 490.625 \text{ cm}^2 \]

  2. Calculate the lateral surface area: \[ \pi r l = 3.14 \times 12.5 \times 22 = 3.14 \times 275 = 865.5 \text{ cm}^2 \]

  3. Add both areas to find the total surface area: \[ \text{Surface Area} = 490.625 + 865.5 = 1356.125 \text{ cm}^2 \]

Therefore, the surface area of the cone is approximately 1,354.125 square centimeters.

The correct answer is 1,354.125 square centimeters.