To calculate the total surface area of a cone, you need to find the area of the base (a circle) and the area of the lateral (side) surface.
1. The radius of the base is half of the diameter, so r = 8/2 = 4 cm.
2. The lateral surface area of a cone is given by πrs, where r is the radius of the base and s is the slant height. In this case, π = 3.14, r = 4 cm, and s = 5 cm.
Lateral surface area = 3.14 * 4 * 5 = 62.8 square cm
3. The base area is given by πr^2.
Base area = 3.14 * 4^2 = 3.14 * 16 = 50.24 square cm
4. The total surface area is the sum of the base area and the lateral surface area.
Total surface area = 62.8 + 50.24 = 113.04 square cm
Therefore, the closest choice to the total surface area is B. 113 square centimeters.
The cone shown has a diameter of 8 centimeters and a slant height of 5 centimeters. Which choice is closest to the total surface area? Use 3.14 to approximate pi.
A. 63 square centimeters
B. 113 square centimeters
C. 126 square centimeters
D. 327 square centimeters
1 answer