🔢 Factors and Multiples
Class 5 Maths · Unit 4 of 12 · about 120 minutes
This unit introduces factors and multiples of whole numbers, along with divisibility rules for 2, 3, 5, and 10. Students will learn to find common factors and common multiples of simple numbers, and to identify prime and composite numbers. These ideas build a foundation for fractions, ratios, and algebra in later grades.
What your child will learn
- Students will be able to list all factors of a given number up to 100.
- Students will be able to list the first several multiples of a given number (up to 10 multiples).
- Students will be able to apply divisibility rules for 2, 3, 5, and 10 to determine if a number is divisible by these.
- Students will be able to find common factors of two numbers up to 100.
- Students will be able to find common multiples of two numbers (within 100).
- Students will be able to identify prime and composite numbers up to 50.
Lessons in this unit
- Finding Factors: Understand what a factor is and find all factors of a number using multiplication pairs and division.
- Finding Multiples: Understand what a multiple is and list multiples of a number by skip counting or multiplication.
- Divisibility Rules for 2, 3, 5, and 10: Learn and apply quick rules to check if a number is divisible by 2, 3, 5, or 10 without doing full division.
- Common Factors: Find common factors of two numbers by listing factors of each and identifying the ones they share.
- Common Multiples: Find common multiples of two numbers by listing multiples and identifying the ones they share.
- Prime and Composite Numbers: Identify prime numbers (exactly two factors) and composite numbers (more than two factors) up to 50.
Key words
- factor
- A number that divides another number exactly, leaving no remainder. For example, 3 is a factor of 12 because 12 ÷ 3 = 4.
- multiple
- The answer you get when you multiply a number by a whole number. For example, multiples of 3 are 3, 6, 9, 12, ...
- divisible
- When one number can be divided by another exactly, with no remainder. For example, 15 is divisible by 5.
- common factor
- A number that is a factor of two or more numbers. For example, 4 is a common factor of 8 and 12.
- common multiple
- A number that is a multiple of two or more numbers. For example, 12 is a common multiple of 3 and 4.
- prime number
- A number that has exactly two factors: 1 and itself. For example, 7 is prime because its only factors are 1 and 7.
- composite number
- A number that has more than two factors. For example, 8 is composite because it has factors 1, 2, 4, and 8.
Help your child at home
What to watch for
- A factor must be smaller than the number, so 12 is not a factor of 12.
- Help: Every number has itself as a factor because 1 × number = number.
- A multiple is always bigger than the number, so 0 is not a multiple.
- Help: 0 is a multiple of every number (0 × n = 0), but we usually start listing from the number itself.
- A number is divisible by 3 if its last digit is 3, 6, or 9.
- Help: For 3, add all the digits. If the sum is divisible by 3, then the number is. Example: 51 → 5+1=6, divisible by 3, so 51 is divisible by 3.
- The common factors are only the numbers that appear in both lists, but 1 is often forgotten.
- Help: Always include 1 because it is a factor of every number.
Try this at home
- Find all factors of 12 using factor pairs
- List the first 5 multiples of 3
- Check if 48 is divisible by 2, 3, 5, 10
- Find common factors of 12 and 18
Quick questions to ask aloud
- How many factors does the number 16 have?
Show answer
The factors of 16 are 1, 2, 4, 8, and 16. That is 5 factors. - What is the 6th multiple of 4?
Show answer
The 6th multiple is 4 × 6 = 24. The multiples are 4, 8, 12, 16, 20, 24. - Which number is divisible by 3? (41 / 52 / 63 / 74)
Show answer
For 63, 6+3=9, and 9 is divisible by 3, so 63 is divisible by 3.
Frequently asked questions
What will my child learn in "Factors and Multiples" (Class 5 Maths)?
Your child will be able to: list all factors of a given number up to 100.; list the first several multiples of a given number (up to 10 multiples).; apply divisibility rules for 2, 3, 5, and 10 to determine if a number is divisible by these.; find common factors of two numbers up to 100.; find common multiples of two numbers (within 100).; identify prime and composite numbers up to 50..
How does MangoMindz teach "Factors and Multiples"?
In 6 short parts (Finding Factors, Finding Multiples, Divisibility Rules for 2, 3, 5, and 10, Common Factors, Common Multiples, Prime and Composite Numbers). Each part has a picture-based lesson read aloud by Mango Teacher, a quick check, and a quiz built from common mistakes children make, with Mango, a study buddy, for questions.
How long does "Factors and Multiples" take?
About 120 minutes in total, spread over 6 parts of 15–25 minutes each.
How can I help my child with "Factors and Multiples" at home?
Work through a small example together, such as: Find all factors of 12 using factor pairs; List the first 5 multiples of 3. Then ask a quick question aloud: How many factors does the number 16 have?
What mistakes do children often make in "Factors and Multiples"?
A factor must be smaller than the number, so 12 is not a factor of 12. Fix: Every number has itself as a factor because 1 × number = number. A multiple is always bigger than the number, so 0 is not a multiple. Fix: 0 is a multiple of every number (0 × n = 0), but we usually start listing from the number itself. A number is divisible by 3 if its last digit is 3, 6, or 9. Fix: For 3, add all the digits. If the sum is divisible by 3, then the number is. Example: 51 → 5+1=6, divisible by 3, so 51 is divisible by 3.
Is "Factors and Multiples" free on MangoMindz?
Yes. Every lesson part and quiz in "Factors and Multiples" is free on MangoMindz, with no ads.