A baker needs to cover a cylinder cake with icing. The cake has a radius of 5 inches and a height of 7 inches. How many square inches of icing will be needed to cover the sides and top of the cake? Icing will not be added to the bottom of the cake. Use 3.14 for pi and round your answer to the nearest tenth.
To find the surface area of the cylinder, we need to find the area of the top and bottom circle, as well as the lateral area.
The area of the top and bottom circle is given by:
A = (pi * radius^2) = 3.14 * 5^2 = 3.14 * 25 = 78.5 square inches (rounded to the nearest tenth).
The lateral area of the cylinder is given by:
A = (circumference * height) = (2 * pi * radius) * height = (2 * 3.14 * 5) * 7 = 31.4 * 7 = 219.8 square inches (rounded to the nearest tenth).
So the total area of icing needed to cover the sides and top of the cake is:
78.5 + 219.8 = 298.3 square inches (rounded to the nearest tenth). Answer: \boxed{298.3}.
To find the surface area of the silo, we need to find the lateral area.
The lateral area of the cylinder is given by:
A = (circumference * height) = (2 * pi * radius) * height = (2 * 3.14 * 4) * 30 = 25.12 * 30 = 753.6 square feet (rounded to the nearest tenth).
So the farmer will need to refinish approximately 753.6 square feet of aluminum. Answer: \boxed{753.6}.
A silo is a large cylinder container that holds hay. A farmer needs to refinish the side of the silo with aluminum. The silo has a radius of 4 feet and a height of 30 feet. How many square feet of aluminum does the farmer need to refinish the silo? He will not be refinishing the top or bottom of the silo. Use 3.14 for pi and round your answer to the nearest tenth.
To find the surface area of the cylinder cake that needs to be covered with icing, we need to calculate the area of the sides and the top of the cake separately.
The formula to calculate the area of the side of a cylinder is given by:
Area of the side = circumference of the base x height
The circumference of the base can be found using the formula:
Circumference of a circle = 2 x pi x radius
For the given cake, the radius is 5 inches. So, the circumference of the base is:
Circumference = 2 x 3.14 x 5 = 31.4 inches (rounded to the nearest tenth)
Now, let's calculate the area of the side of the cake:
Area of the side = 31.4 inches x 7 inches = 219.8 square inches (rounded to the nearest tenth)
Next, we need to calculate the area of the top of the cake. The area of the top is a circle with a radius of 5 inches. The formula to calculate the area of a circle is:
Area of a circle = pi x radius^2
Plugging in the values, we get:
Area of the top = 3.14 x (5 inches)^2 = 78.5 square inches (rounded to the nearest tenth)
To find the total surface area that needs to be covered with icing, we add the area of the side and the top:
Total surface area = Area of the side + Area of the top
Total surface area = 219.8 square inches + 78.5 square inches
Total surface area = 298.3 square inches (rounded to the nearest tenth)
Therefore, the baker will need approximately 298.3 square inches of icing to cover the sides and top of the cake.