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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.
- 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.
- 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?
- Cylinders and Elephants [05/30/1997]
Why are cans always manufactured as cylinders? Are the volume of an
animal and the surface area of its feet related?
- Defining a Sphere [12/1/1994]
We have two math textbooks from different years that give different information about spheres. One says a sphere has one curved face and the other says it has zero. Is one right and the other wrong or has the definition changed?
- A Definition of Geometry [2/1/1996]
A fifth grader asks Dr. Math to give her a definition of geometry.
- 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!
- 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?
- 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.
- Fourth Grade Geometry Questions [4/24/1995]
My grade 4 regular education students are wondering if curved lines can
be parallel lines.
- Geometric Objects [4/1/1996]
Name objects in the real world that suggest geometric figures, including lines and planes.
- Is a Sheet of Paper a 2D or 3D Object? [05/17/2008]
Our teacher said that a piece of paper is a two-dimensional object
that has no height, but some of my classmates and I disagree. We think
a piece of paper still has a height, even if it is very, very, small,
and that it is therefore a three-dimensional object. Who's right?
- Length or Width? [12/02/2003]
Can you please explain the difference between height, length, width
and depth? Is it always the same for each thing?
- Mobius Strips, Spheres, and Dimensionality [05/28/2003]
Is a Mobius Strip 2-D or 3-D? Or is it 1-D? What about a sphere?
- Relative Motion on Face of Earth [05/06/2007]
If I am traveling along the earth's surface at the same rate of speed
that the earth is rotating in the opposite direction then would I
appear to not be moving if you watched me from space?
- Surface Area of a Box [03/06/2003]
How do you find the surface area of a box?
- What is a Torus? [11/30/1999]
Is there a good way to describe a torus to a child?
- What is Geometry For? [03/01/2002]
What is geometry really for?
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