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Browse Elementary School Definitions
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Selected answers to common questions:
Meters squared or square meters?
Greater than, less than symbols.
- Moving the Decimal Point [12/04/2002]
When you divide two decimals, what is it called when you move the
- Multiplier, Sum, Difference, Product, Quotient, Dividend [11/25/1997]
What is a multiplier? an addend? a minuend? a product? Why is the number that is being divided the "dividend"?
- Name of Bar That Denotes a Repeating Decimal [08/30/2004]
What is the name of the bar that goes over a digit or group of digits
that signifies that the digit or group repeats?
- Name of Division Symbol [7/31/1996]
What is the official name for the division symbol?
- Naming Nine Things [01/15/2003]
What is the correct name for nine things collectively? I can only
find the answer up to 7, septuplet, which has been highly publicized
with the McCoy babies.
- Nautical Mph/Knots [08/12/2003]
I want to know how fast the wind is blowing when the weather report
states 5 knots.
- Nonagon or Enneagon? [02/06/2003]
Is 'enneagon' really the correct name for a 9-sided polygon?
- Numbers and Digits [09/21/2000]
What is a digit? Why can't we call a digit a number?
- Numbers and Numerals [09/06/1997]
What's the difference between a number and a numeral?
- Numbers and Numerals [08/29/2002]
15/5 and sqrt(9) both reduce to 3, but is it proper to say that they
- Numbers: Cardinal, Ordinal, Nominal? [10/25/1999]
Which group of numbers - cardinal, ordinal or nominal - does "time" fit
into? Are there other types of numbers as well?
- Number Word Etymologies [05/03/2001]
Who made up the names for numbers?
- Obtuse angles [11/10/1994]
What is an obtuse angle?
- One Dimension [05/13/2003]
Is there such a thing as 1D?
- On-line Mathematics Dictionary [2/18/1996]
I am a 2nd grade teacher in California, and need the list of mathematical
terms I've seen somewhere recently.
- Origin of the Null Symbol [03/05/2003]
Where did the null symbol come from?
- Origin of the Term "Improper" Fraction [07/28/2006]
Why are fractions with larger numerators than denominators called "improper"? Where did the terms "proper" and "improper" originate in relation to fractions?
- Origins of Celsius and Fahrenheit [03/31/2002]
Who invented Celsius and Fahrenheit?
- Parts of a Subtraction Problem [04/09/2001]
What are the numbers 4 and 1 called in the subtraction 4 - 1 = 3?
- A Peck of Peppers [02/27/2002]
If Peter Piper picked a peck of pickled peppers, how many pickled peppers
did Peter Piper pick? How much is a peck?
- Pentagram [12/08/2001]
Is a five-pointed star on a flag a decagon? Or just five triangles?
- Percent or Percentage? [05/14/2002]
Would you please explain the exact difference between the words
percent and percentage?
- Perfect Numbers [08/14/1997]
What is the highest perfect number that has been found? How many perfect
numbers are there? What are they?
- Perfect Square: Definition [10/24/1999]
What is a perfect square?
- Perimeter of an Oval [04/08/1999]
What is the perimeter of an oval called?
- Polygon Names [09/18/2001]
Why is a 3-sided polygon called a triangle instead of a tri-gon? Why is a
4-sided polygon called a quadrilateral instead of a tetragon, when all
the others are ___-gons? Why is there not a single consistent term?
- Polyominos [08/11/1999]
What is the definition of a polyomino?
- The Pound Sign [04/06/2001]
Can the # symbol be used to represent the weight unit 'pounds'?
- Prime Numbers [01/31/1997]
What are the prime numbers and why are they prime numbers?
- Prime Numbers vs. Prime Factors [01/13/1997]
What is the difference between a prime number and a prime factor?
- Pyramid Corners [05/01/2001]
How many corners does a pyramid have? Is a corner the same thing as a
- Quadrant [03/25/2001]
What is a quadrant?
- Quadrilateral Classification: Definition of a Trapezoid [01/15/1997]
What is the correct definition of a trapezoid, and why?
- Quadrilaterals [8/31/1995]
What is 4-sided and has no equal angles?
- Rays and Angles [11/24/1997]
Do rays have an arrow on both ends, or is that an angle?
- Reciprocals [12/19/1996]
What is the use of reciprocals?
- Regular Decagon [03/25/2002]
Can you show me a picture of a regular decagon?
- Rounding to the "Nearer" or "Nearest" Cent? [10/18/2004]
Would you ever say "rounded to the nearer cent" instead of "rounded to the nearest cent"?
- Rules for Significant Figures and Decimal Places [03/23/1999]
Accurate measurement: What are significant digits? When do we use them?
- Significant Digits and Zero [05/19/1999]
When are zeros significant and when are they not significant?