the paper hats are in the shape of a cone. the radius of the cone in 8 cm and the slant height is 20 cm. how many square centimeters of paper are needed to make each hat?
To find the amount of paper needed to make each hat, we need to calculate the lateral surface area of the cone.
The lateral surface area of a cone can be found using the formula: LSA = πrℓ, where r is the radius of the cone and ℓ is the slant height.
In this case, the radius of the cone is 8 cm and the slant height is 20 cm.
So, the lateral surface area of the cone is LSA = π(8)(20) = 160π cm².
To simplify the answer, we can use an approximation for the value of π. Let's take π ≈ 3.14.
Therefore, the lateral surface area of the cone is approximately 160(3.14) = 502.4 cm².
Hence, approximately 502.4 square centimeters of paper are needed to make each hat.