A factor is a number that is divisible by another number and
where the quotient is an integer.
Example
2 is a factor of 18 because the answer is an integer (9). 4 is
not a factor of 18 because the answer is 4 with a remainder of
5.
There are some rules of thumb to easily see if a number is a
factor
2 - an even number is always divisible by two
3 - if the sum of its digits is divisible by 3
5 - if the last digit of the numerator is a 5 or 0 the number is
divisible by 5
6 - if the number is divisible by 2 and 3
10 - if the last digit of the numerator is 0 the number is
divisible by 10
Example
Determine whether 256 is divisible by 2, 3, 4, 5, 6, or 10
A prime number is an integer greater than one that only has two
factors (that it is divisible by), itself and 1 e.g. 2, 3, 5, 7,
11…
A composite number is an integer greater than one that has more
than two factors e.g. the number 4 has the factors 1, 2, 4 and the
number 6 has factors 1, 2, 3, 6. You can express a composite number
in factors of prime numbers e.g. 4 = 2 2
The numbers 0 and 1 are considered neither composite numbers nor
prime numbers.
Example:
Video lesson: Factorize the expression
