Ask Dr. Math

Elementary School Archive

Browse Elementary School Definitions
Stars indicate particularly interesting answers or good places to begin browsing.

Selected answers to common questions:
    Meters squared or square meters?
    Greater than, less than symbols.

---

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 are integers?

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 vertex?

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? Why?

Significant Digits and Zero [05/19/1999]

When are zeros significant and when are they not significant?

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 problems.

Page: [<prev]  1  2  3  4 [next>]