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3D and higher
Browse Elementary School Definitions
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Selected answers to common questions:
Meters squared or square meters?
Greater than, less than symbols.
- Simple Closed Curve [05/22/2001]
Why is a simple closed curve called just that?
- Square Numbers [07/27/1999]
Can you explain what a square number is?
- Story Problems: Real, Realistic, Theoretical [10/24/2002]
I am trying to get the definitions for theoretical, realistic, and
real problems to be able to determine different types of story
- Subtrahend and Minuend [03/10/1997]
What are subtrahend and minuend? I think they have to do with
- Symmetry [04/29/2001]
What is symmetry?
- Telling Time: A.M. and P.M. [10/30/2001]
What do A.M. and P.M. mean?
- Three IS Greater Than Two? [10/21/2002]
Should we say '3 greater than 2' or '3 IS greater than 2'?
- Trilogy, Tetralogy... [05/28/2003]
Why isn't there a numbering system for groups like trilogies?
- Truncating [01/19/2002]
What does truncating mean?
- Types of Triangles [02/24/2003]
What is the the difference between equilateral, isosceles, and
scalene triangles? How can I remember which name goes with which
- Use and Meaning of 'And' in Naming Decimals [12/01/2004]
Can you please tell me what the word "and" means in the word form of a
- Vertical Angle [11/15/2001]
What are vertical angles? Are they equal?
- What Does a Twofold Increase Mean? [01/23/2004]
Is a twofold increase simply twice the amount? What about a threefold
increase? I'm not used to this terminology of using 'fold.' Does it
refer to powers or multiples?
- What is a Multiple? [12/4/1995]
What is the definition of a multiple?
- What is a Parenthesis? [07/17/2000]
What does the mathematical term "parenthesis" mean?
- What is a Set? [04/04/1997]
What is the correct term to refer to groups of objects like 3 cars, 7
pencils, or 5 apples?
- What is a Sign? [04/21/2003]
Can you do anything in math without signs?
- What is a Significant Digit? [12/25/2001]
I came across a question asking for an answer with no more than "2
significant digits" - can you please explain what a significant digit is?
- What is a tessellation? [01/20/1997]
Can you give an example?
- What is a Torus? [11/30/1999]
Is there a good way to describe a torus to a child?
- What is a Vertex? [12/06/2001]
And what does vertices mean?
- What is Circumference? [06/25/2001]
My friend told me it's somewhat like the measurement of the outside of a
circle, but I don't understand that.
- What is Length in a Rectangle? [05/31/1999]
Is the length of a rectangle the longest side, whether vertical or
- What is the Plural of Rhombus? [4/7/1995]
Hi! Say, what exactly is the plural of "rhombus?" We aren't sure if it is
"rhombi" or "rhombuses".
- Who Invented the Square Root? [12/11/1996]
I've only seen long, stringy roots!
- Whole Numbers and Multiples [09/11/2001]
My students and I have been trying to figure out what numbers are in the
set of "Whole Numbers." Is zero a whole number?
- Why Does 1 Degree Equal 60 Minutes? [07/28/2004]
In 60 minutes, the minute hand of a clock makes a full circle, which
is 360 degrees. How can 60 minutes equal 1 degree when measuring angles?
- Why Is a Circle 360 Degrees? [07/01/1998]
Why is a circle defined as 360 degrees?
- Why Is 'Pound' Abbreviated 'lb'? [03/08/2004]
Why is "pound" abbreviated lb? Is it because of its Latin roots? I know libra means pound. What is the history of it?
- Why is the Word "Number" Abbreviated to "No."? [05/13/2002]
Why is the word number abbreviated to no.?
- Word for a 225th Birthday [07/10/2001]
This year America is celebrating its 225th birthday. As we celebrated the
bicentennial in 1976, is there a term for 225 years?
- Writing Numbers with Hyphens [06/04/2003]
Why do we hyphenate one hundred-millionth, but we don't hyphenate one