#1
Which of the following is true about a cube?
All faces are squares
ExplanationEach face of a cube is a square.
#2
What is the sum of the interior angles of a tetrahedron?
360 degrees
ExplanationThe sum of interior angles of any polygon is 180 * (n - 2) degrees, where n is the number of sides. A tetrahedron has 4 faces, so the sum of its interior angles is 180 * (4 - 2) = 360 degrees.
#3
What is the volume of a cube with side length 5 units?
125 cubic units
ExplanationThe volume of a cube is calculated as side length cubed, so for a cube with side length 5 units, the volume is 5 * 5 * 5 = 125 cubic units.
#4
How many faces does a dodecahedron have?
12
ExplanationA dodecahedron has 12 faces.
#5
What is the surface area of a cylinder with radius 4 units and height 6 units?
48π square units
ExplanationThe surface area of a cylinder is calculated as 2πrh + 2πr^2, where r is the radius and h is the height. Substituting r = 4 and h = 6 gives 48π square units.
#6
Which of the following statements about a cone is true?
It has a circular base
ExplanationA cone has a circular base.
#7
What is the name of a three-dimensional shape with 12 edges and 8 vertices?
Octahedron
ExplanationAn octahedron is a polyhedron with 12 edges and 8 vertices.
#8
If the length, width, and height of a rectangular prism are all different, how many distinct diagonals does it have?
12
ExplanationA rectangular prism has 12 distinct diagonals when all its sides are different in length.
#9
What is the total number of edges in a triangular prism?
9
ExplanationA triangular prism has 6 edges on its lateral faces and 3 edges connecting its bases, totaling 9 edges.
#10
Which of the following is a property of a regular pyramid?
All edges are equal in length
ExplanationIn a regular pyramid, all edges are of equal length.
#11
What is the total number of diagonals in a regular octahedron?
24
ExplanationA regular octahedron has 12 vertices, so there are 12 * (12 - 1) / 2 = 66 total diagonals, but each diagonal connects two vertices, so we divide by 2 to get the number of diagonals, which is 33. However, there are 12 edges, which are not counted as diagonals, so the total number of diagonals is 33 - 12 = 21. Since each diagonal connects two vertices, we have counted each diagonal twice, so we divide by 2 to get the final answer: 21 / 2 = 10.5, which we round to 11. So, a regular octahedron has 11 diagonals.
#12
If the lengths of all edges of a regular tetrahedron are tripled, how many times does its volume increase?
27 times
ExplanationIf the lengths of all edges of a regular tetrahedron are tripled, its volume increases by a factor of 3^3 = 27.
#13
Which of the following is not a polyhedron?
Sphere
ExplanationA sphere is not a polyhedron because it does not have flat faces.
#14
What is the maximum number of faces shared by two tetrahedra?
4
ExplanationTwo tetrahedra can share up to 4 faces.
#15
Which of the following statements about a sphere is true?
It has no vertices
ExplanationA sphere is a perfectly round geometrical object in three-dimensional space, and it does not have any vertices.
#16
What is the name of a three-dimensional shape with 20 faces and 12 vertices?
Icosahedron
ExplanationAn icosahedron is a polyhedron with 20 faces and 12 vertices.
#17
How many faces does a pentagonal pyramid have?
6
ExplanationA pentagonal pyramid has 6 faces.