Marco is baking a cake for a party. The cake is in the shape of a right circular cylinder. He needs to buy frosting for the cake but doesn’t know the surface area of the cake. If the diameter of the cake pan is 13 inches, and the height is 4 inches, what is the surface area he needs to frost? Use 3.14 for π .(1 point)
Responses
163.28 inches2
163.28 inches squared
428.61 inches2
428.61 inches squared
265.33 inches2
265.33 inches squared
1,287.88 inches2
To find the surface area of the right circular cylinder, you need to find the lateral surface area and the area of the top and bottom circles separately.
Lateral Surface Area = 2πr*h, where r is the radius (half of the diameter) and h is the height.
r = 13/2 = 6.5 inches
h = 4 inches
Lateral Surface Area = 2 * 3.14 * 6.5 * 4
Lateral Surface Area = 163.28 inches2
Area of the top and bottom circles = 2 * π * r^2
Area of the top and bottom circles = 2 * 3.14 * 6.5^2
Area of the top and bottom circles = 2 * 3.14 * 42.25
Area of the top and bottom circles = 265.33 inches2
Total Surface Area = Lateral Surface Area + Area of top and bottom circles
Total Surface Area = 163.28 + 265.33
Total Surface Area = 428.61 inches2
Therefore, Marco needs 428.61 inches squared of frosting for the cake.