All SAT II Math II Resources
Example Questions
Example Question #2 : Surface Area
A water tank takes the shape of a closed rectangular prism whose exterior has height 30 feet, length 20 feet, and width 15 feet. Its walls are one foot thick throughout. What is the total surface area of the interior of the tank?
The height, length, and width of the interior tank are each two feet less than the corresponding dimension of the exterior of the tank, so the dimensions of the interior are 28, 18, and 13 feet. The surface area of the interior is what we are looking for here. It comprises six rectangles:
Two with area square feet;
Two with area square feet;
Two with area square feet.
Add:
square feet.
Example Question #1 : Surface Area
What is the surface area of a cube with a side length of 5?
If you were to take apart a cube so that you could lay it flat on a surface, you would be able to see that a cube is just made up of 6 identical squares. The area of one square is the length of the side squared, so the surface area of the cube would be denoted with the formula:
In this case the side length is 5, so plugging that into the formula will get the answer.
Example Question #3 : Surface Area
Find the surface area of a rectangular prism with length, width, and height dimensions of , , and , respectively.
Be careful not to confuse surface area with volume!
There are 6 faces in a rectangular prism, and we will need the sum of all the areas of each face.
Write the formula.
Substitute the dimensions.
Evaluate each product in the bracket.
Combine the terms of the numerator.
The answer is:
Example Question #101 : Geometry
What is the surface area of a cube with a side length of ?
Write the formula for the surface area of a cube.
Substitute the side length.
The answer is:
Example Question #1 : Surface Area
Find the surface area of a sphere with a radius of 3.
Write the formula for the surface area of a sphere.
Substitute the radius into the equation.
The answer is:
Example Question #2 : Surface Area
Find the surface area of a sphere with a radius of 2.
Write the formula for the surface area of a sphere.
Substitute the radius.
The answer is:
Example Question #1 : Surface Area
Find the surface area of a cube if the area of one of the square faces is .
Write the formula for the surface area of a cube.
The area of a square side is already given. Substitute that as the term.
The answer is:
Example Question #21 : 3 Dimensional Geometry
A regular tetrahedron has four congruent faces, each of which is an equilateral triangle.
The total surface area of a given regular tetrahedron is 600 square centimeters. To the nearest tenth of a centimeter, what is the length of each edge?
The total surface area of the tetrahedron is 600 square centimeters; since the tetrahedron comprises four congruent faces, each has area square centimeters.
The area of an equilateral triangle is given by the formula
Set and solve for :
centimeters.
Example Question #2 : Faces, Face Area, And Vertices
A regular octahedron has eight congruent faces, each of which is an equilateral triangle.
The total surface area of a given regular octahedron is 400 square centimeters. To the nearest tenth of a centimeter, what is the length of each edge?
The total surface area of the octahedron is 400 square centimeters; since the octahedron comprises eight congruent faces, each has area square centimeters.
The area of an equilateral triangle is given by the formula
Set and solve for :
centimeters.
Example Question #1 : Faces, Face Area, And Vertices
A regular icosahedron has twenty congruent faces, each of which is an equilateral triangle.
A given regular icosahedron has edges of length four inches. Give the total surface area of the icosahedron.
The area of an equilateral triangle is given by the formula
Since there are twenty equilateral triangles that comprise the surface of the icosahedron, the total surface area is
Substitute :
square inches.