Factors

1
Factors

• Finding the numbers that make a multiplication
  fact for a product

2
What is a factor?

• A factor is one of the numbers that when
  multiplied, result in a product.

Example 3 x 4 12 factor
factor product
3
How to find factors?

• Find factors by finding out what numbers a
  certain number is divisible by.

• Example
• 18
• It is divisible by 1 and 18 because any number
  is divisible by itself and one
• It is even, so it is divisible by 2
• Its digits can be added to a sum of 9, so it is
  divisible by 3 and 9
• It is divisible by 6 because it is divisible by
  both 2 and 3

So the factors of 18 are 1, 2, 3, 6, 9, 18
4
Another way to find factors

• Another way to find the factors of a number is to
  find its prime factorization.
• Once you do this, you can multiply any two
  numbers together to find the factors of that
  number.

So the factors are 1 (always) 2 (2x1) 3
(3x1) 6 (3x2) 9 (3 x 3) 18 (3x3x2)
Prime Factorization of 18 18 9 x 2 1 x 3 x 3 x
2 (one is always a factor but not written
normally in a prime factorization)