Question

A cone-shaped megaphone has a radius of 15 centimeters and a slant height of 20 centimeters. A megaphone has an open bottom. What is the lateral surface area of the megaphone, in square centimeters? Use 3.14 for pi.(1 point) Responses 109.9 square centimeters 109.9 square centimeters 1,884 square centimeters 1,884 square centimeters 1,648.5 square centimeters 1,648.5 square centimeters 942 square centimeters

Answer 1

To find the lateral surface area of the cone-shaped megaphone, we can use the formula for the lateral surface area of a cone, which is:

\[ A = \pi r l \]

where \( A \) is the lateral surface area, \( r \) is the radius, and \( l \) is the slant height.

Plug in the given values:

• Radius (\( r \)) = 15 cm
• Slant height (\( l \)) = 20 cm
• Using \( \pi \approx 3.14 \)

Now calculate the lateral surface area:

\[ A = 3.14 \times 15 \times 20 \]

Calculating \( 15 \times 20 \):

\[ 15 \times 20 = 300 \]

Now substitute back into the area formula:

\[ A = 3.14 \times 300 \]

Calculating \( 3.14 \times 300 \):

\[ A = 942 \text{ square centimeters} \]

The lateral surface area of the megaphone is 942 square centimeters.