GCF

• To find the greatest common factor (GCF) between two numbers:
• Finding the GCF

  1. List the factors of each number

  2. Identify the common factors

  3. The greatest common factor is the largest of the common factors
• Factor

  A number that can multiply with another number to give the original number
• Factors of 10

  • 1
  • 2
  • 5
  • 10
• Factors of 15

  • 1
  • 3
  • 5
  • 15
• Prime number


  A number with only 1 and itself as factors
• Composite number


  A number with more than 1 and itself as factors