Basic Math Terms Every Student Needs To Know
(By Topics)

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Here is a list basic Math Terms arranged by Topics. I hope you find it useful.


Number Sense

Click here to go to the Number Sense topic.

Numerals

These are numbers written in symbols (ex. 1, 2, 3...) in contrast to numbers written in words (ex. one, two, three...).

Counting Numbers

These are consecutive numbers starting from 1 (ex. 1, 2, 3...). Click here to learn more on Counting Numbers.

Number Line

A number line is a horizontal line with markings to show the position of numbers relative to each other.

The numbers on the right of the line are bigger than the numbers on the left.

Even Number

An even number is a number with the digit 0, 2, 4, 6 or 8 in the 'ones' place. Examples of even numbers: 4, 20, 38, 1110, 2378
(See Place Value)

Odd Number

An odd number is number with the digit 1, 3, 5, 7, or 9 in the 'ones' place. Examples of odd numbers: 5, 11, 45, 267, 4209, 9000.
(See Place Value)

Ordering Numbers

To write numbers in order means to write them in a particular sequence, either in ascending order (from small to big) or descending order from big to small).

Click here for learning materials.

Ascending Order


Writing numbers in ascending order means writing the number in order of size starting with the smallest. You can think of ascending order as going up a flight of stairs or getting bigger.

Descending Order

Writing numbers in descending order means writing the number in order of size starting with the biggest. You can think of descending order as going down a flight of stairs or getting smaller.

Consecutive Numbers

This Math term refers to numbers that appear in running order (ex. 10, 11, 12...). The difference between each consecutive number is one.

Consecutive Even Numbers

These are even numbers that appear in running order (ex. 2, 4, 6...). The difference between each consecutive even number is two.

Consecutive Odd Numbers

These are odd numbers that appear in running order (ex. 7, 9, 11...). The difference between each consecutive odd number is two.

Ordinal Numbers

These are numbers that refer to position. They can be written as numerals (ex. 1st, 2nd, 3rd...) or words (ex. first, second, third...)

Place, Place Value

These 2 Math terms explain how numbers are formed.

Numbers are made up of digits (0, 1, 2, 3, 4, ... 9). The value of each digit depends on its place or position.

For instance, the digit 2 in the 'tens' place has a value of twenty and a value of two if it is in the 'ones' place. 

Table of Contents

Addition

Addend

An addend is a number on the left hand side of an Addition Math sentence or equation. In this example: 21 + 52 = 73, the addends are 21 and 52.

Addition, Add

Addition is a basic Math operation.  To add means to combine numbers to form a bigger number. When we add, the addends are always smaller than the sum.


More Than

This Math term occurs often in problem sums. 'More ... than' also means 'bigger than' or 'in excess of' or 'extra'.

If John has more stickers than George, this means the number of John's stickers is bigger than the number of George's stickers.

We usually, but not always, use addition with the term 'more ... than' in a problem sum.

Subtraction

Difference

You find the difference of 2 numbers by subtracting the smaller number from the bigger (ex. the difference of 2 and 10 is 8. The difference of 10 and 2 is also 8).

Less Than

This Math term occurs often in problem sums. 'Less ... Than' or 'fewer ... than' means 'smaller than'.

If John's height is less than George's height, it means the number for John's height is smaller than the number for George's height.

We usually, but not always, use subtraction with the term 'less .. than' in a problem sum.

› Math Terms (Topical)

Multiplication

Multiply, Multiplication or Times

Multiply means groups of the same numbers.We can think of multiplication in 2 ways.

For example: 2 x 5 can mean 2 groups of 5 or two 5's. This is the same as 5 + 5.

                   2 x 5 = 5 + 5

(This way of thinking about multiplication is very useful when working on problem sums.)


Or 2 x 5 can also mean 2 in a group, 5 groups altogether. This is the same as 2 + 2 + 2 + 2 + 2.

                 2 x 5 = 2 + 2 + 2 + 2 + 2

Multiple

A multiple is the result of a multiplication.

For example, the third multiple of 6 is 18 (the result of multiplying 3 and 6).

Another example: The question "Is 24 a multiple of 5?" really means
"Can 5 be multiplied by any number to give the answer 24?"

If the answer is yes, than 24 is a multiple of 5.

If the answer is no, then 24 is not a multiple of 5. 
(See also Factor.)

Common Multiple

A common multiple is a multiple that occurs in all the numbers being compared. There is an infinite number of common multiples between numbers.

Take note that the first multiple of any number is the number itself. (Ex. 3 is the first multiple of 3, 6 is the first multiple of 6 and so on.)


Example: What are the first 5 common multiples of 2 and 3? 

     Multiples of 2 = 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30 ...
     Multiples of 3 = 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, ...

Answer: 6, 12, 18, 24, 30

LCM (Lowest Common Multiple)

When we want the LCM or Lowest Common Multiple of 2 or more numbers, we want the first multiple that occurs in all the numbers being compared.

So the LCM of 2 and 3 is 6.

Product

This Math term refers to the result of multiplication.

For example, the product of 5 and 8 is 40. (5 x 8 = 40)
(See Multiply, Multiplication, Times)


Division

Division

Division is a Math operation where you arrange (divide) a number into groups of smaller numbers. It is the opposite of multiplication.

There are 2 ways to think about division.


Example: "18 divided by 3 equals 6" can mean if you arrange 18 items into 3 groups you will get 6 items in each group.

Or it can mean if you arrange 18 items into groups of 3, you will get six groups.

Dividend, Divisor, Quotient, Remainder

These Math terms relate to division. See the graphics below.

Divisible

This Math term refers to division.


If we ask "Is 26 divisible by 3?" what we mean is "Can 26 be divided by 3 without leaving any remainder?"


If the answer is yes, than 26 is divisible by 3.
If the answer is no, then 26 is not divisible by 3. 

26 is not divisible by 3 because there is a remainder of 2.

Factor

This Math term is similar to the term divisible.

If we want to know whether 2 is a factor of 25, what we really want to know is
"Can 25 be divided by 2 without leaving any remainder?"

If the answer is yes, than 2 is a factor of 25.
If the answer is no, then 2 is not a factor of 25.

So now we know that 2 is not a factor of 25 because there is a remainder of 1 when we divide 25 by 2.

To find out whether one number is a factor of another, we have to divide the second number by the first.


If the result is a whole number with no remainder, then the first number is a factor of the second. 


The number 1 is a factor of all numbers. Any number that has only 2 factors is called a prime number (ex. 2, 3, 5...)

Common Factor

Sometimes we want to find the common factors of two or more numbers. A common factor is a factor that occurs in all the numbers being compared.

There is a fixed number of common factors between numbers.


Example: What are the common factors of 12 and 30? 

     Factors of 12 = 1, 2, 3, 4, 6, 12
     Factors of 30 = 1, 2, 3, 5, 6, 10, 15, 30

Answer: 1, 2, 3, 6


GCF (Greatest Common Factor) or HCF (Highest Common Factor)

These 2 Math terms have the same meaning.

If you want to find the GCF or HCF of a few numbers, you first find all the possible factors of each number.

Then you choose the biggest factor that can be found in each number.

Example: Find the HCF of 24 and 30.

    Factors of 24 = 1, 2, 3, 4, 6, 8, 12, 24
    Factors of 30 = 1, 2, 3, 5, 6, 10, 15, 30

The GCF (or HCF) of 24 and 30 is 6.

› Math Terms (Topical)

Fractions

Fraction

There are two ways to look at fractions.

One way is to think of breaking up a whole piece into smaller equal pieces. So half a cake means cutting a cake into 2 equal parts and taking only 1 of the parts.Or one piece out of two pieces.

This way is called 'parts of a whole'. 
The important thing to remember is that each piece must be of the same size as every other piece.

Another way to look at fractions is 'parts of a group' of items. In this case, each part does not have to be the same size. If there are 5 people in a room, two-fifths of them would mean 2 people (or 2 out of 5).

Fractions and division are related operations since we are breaking up a large number into smaller numbers.

Denominator

This Math term applies to a fraction. It is the bottom number in a fraction.  The top number in the fraction is called the numerator.

The numerator tells us the number of parts we want and the denominator tells us the total number of parts.

Numerator

This Math term applies to a fraction. 

It is the top number of a fraction.
The bottom number is called the denominator.

The numerator tells us the number of parts we want and the denominator tells us the total number of parts.

› Math Terms (Topical)