Divisibility Rules for 3, 6, and 9

Divisibility Rules

Divisibility Rule Of 3

• A number is divisible by 3 if the sum of its digits is divisible by 3.
• Example: 123 is divisible by 3 because 1 + 2 + 3 = 6, which is divisible by 3.

Divisibility Rule Of 6

• A number is divisible by 6 if it is divisible by both 2 and 3.
• A number is divisible by 2 if it ends in 0, 2, 4, 6, or 8.
• Combine the rules for 2 and 3 to check for divisibility by 6.

Divisibility Rule Of 9

• A number is divisible by 9 if the sum of its digits is divisible by 9.
• Example: 918 is divisible by 9 because 9 + 1 + 8 = 18, which is divisible by 9.

Finding Common Factors

• To find common factors, list the factors of each number and identify the common factors.
• Example: Find the common factors of 12 and 15.
  • Factors of 12: 1, 2, 3, 4, 6, 12
  • Factors of 15: 1, 3, 5, 15
  • Common factors: 1, 3

Prime Factorization

• Prime factorization is the process of expressing a number as a product of prime numbers.
• Example: Find the prime factorization of 24.
  • 24 = 2 × 2 × 2 × 3
  • Prime factors: 2, 2, 2, 3

Divisibility Rules

Divisibility Rule Of 3

• A number is divisible by 3 if the sum of its digits is divisible by 3.
• This rule can be applied to any number, regardless of its size.

Divisibility Rule Of 6

• A number is divisible by 6 if it is divisible by both 2 and 3.
• To check for divisibility by 6, apply the rules for 2 and 3 separately.
• A number is divisible by 2 if it ends in 0, 2, 4, 6, or 8.
• Combine the rules for 2 and 3 to check for divisibility by 6.

Divisibility Rule Of 9

• A number is divisible by 9 if the sum of its digits is divisible by 9.
• This rule can be applied to any number, regardless of its size.

Finding Common Factors

• To find common factors, list the factors of each number and identify the common factors.
• This method can be applied to find common factors of any two numbers.

Prime Factorization

• Prime factorization is the process of expressing a number as a product of prime numbers.
• This method can be applied to find the prime factors of any number.
• The prime factors of a number are the prime numbers that multiply together to give the original number.

Learn the rules to determine if a number is divisible by 3, 6, or 9. Understand how to apply the rules to check for divisibility.