Question

NEED HELP GEOMETRY ASAP

Answer 1

Answer:

1. The circumference of the circular base of the conical hat is 52.36 inches

2. The surface area of the cone that needs to be covered is  262 in.²

Step-by-step explanation:

Here we have that the given parameters are;

Diameter, D of circular = 20 in. = 2 × radius R, of the circle

R = 10 in.

Cut out section of cut out sector of circle = 60°

Therefore, circumference of the circular base = π×D×(360 - 60)/360 which gives;

The circumference of the circular base of the conical hat = π×20×(30)/36 = π·50/3 = 52.36 in.

Therefore, the radius of the formed cone = π·50/3/(2·π) = 25/3 = $8\tfrac{1}{3}$ = 8.33 in.

The formed cone satisfies the equation;

R² = h² + r²

Where:

h = Height of the cone

r = radius of the cone

∴ 10² = h² + 8.33²

∴ h² = 10² - 8.33² = 30.56 in.

The lateral surface area of the cone = π×r×l where l = R, we therefore have;

The lateral surface area of the cone = π×8.33×10 = $\pi \cdot 8\tfrac{1}{3}$ = 261.8 in.² = 262 in.².

The surface area of the cone that needs to be covered = The lateral surface area of the cone = 262 in.².