Basic Mathematics

Natural Numbers: all non-fractional numbers excluding zero.

(1, 2, 3, 4 …)

Whole Numbers: all non-fractional numbers including zero.

(0, 1, 2, 3, …)

Integers: all non-fraction whole numbers and their negatives.

(…, -3, -2, -1, 0, 1, 2, 3 …)

Rational Numbers: all integers in the form of p/q (fraction) where p and q are positive or negative integers and q is not equal to zero.

(½, ¾, …)

Irrational Numbers: any number that is not a rational number and when expressed in decimal form is neither terminating (stops after a few decimal places) nor repeating (the same digit repeats indefinitely after decimal point). Irrational numbers can also be expressed in the form of fractions.

(√2, √4)

Real Numbers: all rational and irrational numbers combined are called real numbers.

Even Numbers: all numbers divisible by 2 (including 0).

(0, 2, 4, 6, 8 …)

Odd Numbers: all numbers not divisible by 2.

(1, 3, 5, 7, 9 …)

Prime Numbers: a number that can only be divided by 1 and itself (excluding 0 and 1).

(3, 5, 7, 11 …)

Composite Numbers: natural numbers greater than 1 which are not prime numbers.

Factor of A Number: any integer by which another number is completely divisible.

16 is divisible by 2, 4, 8 and 16, thus they factors of that number.

Highest Common Factor or Greatest Common Divisor: The greatest common divisor, also known as the GCD, is the largest positive integer that divides two or more positive integers without leaving a remainder.

8 is the highest number that can divide both 16 and 24

Lowest Common Multiple: The smallest or least positive integer that is divisible by both a and b is called the LCM.

48 is the smallest number divisible by both 16 and 24