3D and higher
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3D and higher
Browse Middle School 3D and Higher Geometry
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Selected answers to common questions:
Do cones or cylinders have edges?
- Area and Volume [04/10/2002]
I cannot figure out how to do volume.
- Does a Cone have an Edge? A Vertex? [03/12/2002]
Our 4th grade math textbook defines a cone as "A solid figure with one
circular face and one vertex." This sounds reasonable until you read the
textbook's definitions for face, edge, and vertex.
- Number of Cylinder Edges [04/01/2002]
My son was asked "how many edges are there on a solid cylinder?" on a
recent math examination. His answer was "2" and it was marked incorrect.
- Three-dimensional Plane Diagrams [03/10/1999]
Draw: two parallel planes with another plane intersecting them; two
parallel planes with an intersecting line.
- Volume equations for a sphere and pyramid [6/10/1996]
I am now thoroughly confused: we just learned the formulas for volume of
a sphere and volume of a pyramid, but, he wouldn't tell me how to do it.
- The Volume of a Cylinder [11/8/1995]
What is the formula for computing the volume of a cylinder?
- Volume of the Sphere [11/4/1994]
I am an eighth grader. Could you please tell me what the volume of a
sphere is? How can I calculate it?
- Adding a 6-Inch Layer of Gravel [03/13/2003]
Your company is constructing a soccer field for a high school. The
field is 110 yards long and 80 yards wide...
- Area and Volume of a Pear [6/4/1996]
How do you find the area and volume of a pear?
- Area, Surface Area, and Volume: How to Tell One Formula from Another [01/18/1999]
Unit dimensions -- and even an idea from calculus -- can tell you which
formula you're using.
- Bases and Faces [12/05/2001]
I can't figure out the difference between a base and a face on the shapes
we are learning.
- CADAEIBFEC and Other NCTM Questions [10/27/1998]
CADAEIBFEC is a mnemonic for an important piece of mathematical
information. What is it?
- Circles and Squares [4/3/1996]
Given a large circle with a square inside it (the sides of the square are
equal to the radius of the larger circle and are chords of the circle)
and a smaller circle inside the square...
- Comparing Volume and Surface Area [05/01/2002]
Why is it that the surface area of a given rectangular solid can
sometimes be greater than the volume of that solid?
- Connection Between Circumference and Surface Area [05/08/1998]
Can you explain the connection between the circumference of a circle and
the surface area of a sphere?
- Converting Between Cubic Feet and Cubic Yards [05/09/2002]
How can I figure out how many cubic feet are in a cubic yard?
- Cubic Centimeter, Cubic Inch [08/26/1997]
Can you help me define these terms?
- Cups and Volume [12/06/2001]
How can I calculate the volume of a box, if I know how many cups of rice
fill it? And how can 2 cups be a volume measure?
- Cutting a Cake into 8 Pieces with 3 Cuts [09/08/2002]
How do you cut a cake into 8 pieces making only 3 cuts? How do you cut
a doughnut into 12 pieces with only 3 cuts?
- Cylinder Height, Area, Volume [04/07/2003]
Why does the volume of a cylinder get larger as the radius gets larger
and the height gets smaller?
- Cylinder Volume [6/30/1996]
What is the formula for the volume of a cylinder?
- Defining Distance Mathematically [10/16/1996]
What is wrong with D' = sqrt(X^2 - X'2)?
- Definition For Cylinder without Big Words [11/03/1998]
I just need a good definition for cylinder that I can understand.
- Definition of a Parellelepiped [9/18/1995]
What is a parallelepiped?
- Definitions of Cones and Cylinders [03/02/2004]
Are cones and cylinders pyramids, prisms or neither? My 5th grade
geometry class cannot reach an agreement on this subject!
- Degrees in a Sphere? Steradians [09/27/2001]
If one can say that a circle contains 360 degrees, how many degrees can
one say are in a sphere?
- Depth of a Tank [09/04/1997]
A tank 100' long and 10' wide holds 15,000 cu. ft. of water...
- Diameter of the Base of a Cone [08/12/1998]
How do you find the formula to calculate the diameter of the base of a
cone of nine degrees at various lengths?
- Dimensions [08/30/2001]
What are 1-dimensional, 2-dimensional, and 3-dimensional? What's the
- Dimensions of a Cardboard Box [09/28/1997]
A box with a square bottom and a volume of 2000 centimeters can be made
by cutting 5-centimeter squares from the corners of a piece of
- Distance Between Opposite Corners of a Box [05/09/2002]
A moth is sitting in the lower left front corner of a storage shed.
What is the length of the shortest path that the moth can fly to the
upper right back corner of the shed?
- Does a Sphere have Sides? [04/20/2001]
How many sides does a sphere have?
- Earth - an Oblate Spheroid [05/17/1999]
Where can I find real-life examples of an ellipsoid?
- Edge of a Cube Given Volume [10/06/1997]
I am a teacher currently teaching volume to a class of Grade 5 pupils.
- Edges vs. Corners [04/18/2002]
My students get confused on how to determine an edge versus a corner,
and counting the number of edges on a geometric figure, say a cube.
- Einstein, Curved Space, and Pi [10/09/1999]
If space is curved and Euclidean geometry doesn't apply, doesn't that
mean that the value of pi changes and can sometimes be rational?
- Etymologies of Algebra, Geometry, Trigonometry [10/22/2001]
What are the origins and roots of the words geometry, algebra, and
- Euclid's Parallel Postulate [2/14/1995]
We are studying Euclid's Parallel Postulate. Why did mathematicians
disagree with him? What other geometries resulted from this disagreement?
What postulate replaced the Parallel Postulate?
- Explanation of the Formula for the Volume of a Pyramid [06/16/2005]
Can you explain WHY the formula for the volume of a pyramid is
- Figuring Out Formulas for Area [08/24/1999]
How can I remember formulas for squares, triangles, cylinders, etc?