Question

what is the surface area of the cone? use 3.14 for pi.
slant height = 22 cm
diameter = 25 cm

Answer 1

A spyglass in the shape of a cone has a slant height of 18 centimeters and a radius of 6 centimeters. What is the surface area of the spyglass? Use 3.14 for pi

Answer 2

To find the surface area of a cone, you need to calculate both the lateral surface area (the curved part) and the base area.

First, let's find the radius of the cone:
The diameter is given as 25 cm, so the radius is half of that:
radius = diameter / 2 = 25 cm / 2 = 12.5 cm

Now, let's find the lateral surface area:
Lateral surface area = π × radius × slant height
= 3.14 × 12.5 cm × 22 cm
= 868.5 cm²

Next, let's find the base area:
The base area of a cone is given by: π × radius²
= 3.14 × (12.5 cm)²
= 3.14 × 156.25 cm²
= 490.625 cm²

Finally, add the lateral surface area and the base area to get the total surface area of the cone:
Total surface area = Lateral surface area + Base area
= 868.5 cm² + 490.625 cm²
= 1359.125 cm²

Therefore, the surface area of the cone is approximately 1359.125 cm².

Answer 3

To find the surface area of the spyglass, we need to calculate both the lateral surface area and the base area.

First, let's find the lateral surface area:
Lateral surface area = π × radius × slant height
= 3.14 × 6 cm × 18 cm
= 339.12 cm²

Next, let's find the base area:
The base area of a cone is given by: π × radius²
= 3.14 × (6 cm)²
= 113.04 cm²

Finally, calculate the total surface area by adding the lateral surface area and the base area:
Total surface area = Lateral surface area + Base area
= 339.12 cm² + 113.04 cm²
= 452.16 cm²

Therefore, the surface area of the spyglass is approximately 452.16 cm².