Answer:
About 75 in²; Aubrey found the surface area of the cone and included the base.
Complete question:
Aubrey is making cone-shaped hats for a birthday party. She mistakenly thinks that she will need about 104 square inches of paper for each hat.Cone with diameter six inches and slant height eight inches.What is the correct amount of paper Aubrey will need per hat? Explain Aubrey’s mistake. Use 3.14 for π and round to the nearest inch.
Step-by-step explanation:
Lateral surface area of a cone = Paper required to for each hat
Lateral surface area = πrl
where, r is radius of the cone and l is lateral height of the cone
Lateral surface area = π(3)(8)
= 75.36 square inches
≈ 75 square inches
Therefore, total paper required for each cap is about 75 square inches.
Total surface area of the cone (Lateral area + Area of the base)
= πr(r + l)
= 3.14(3)(3 + 8)
= 103.62
≈ 104 square inches.
Aubrey did a mistake by finding the total surface area (including base area) of the cone instead of lateral surface area.
