Free · Class 4–6 · 3 worksheets · answer keys · practise online · set 20

Prime and composite numbers worksheets

Free prime and composite numbers worksheets for Class 4 to 6: prime or composite, primes between two numbers and prime factorisation — with answers.

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Prime or composite? (Class 4–5)Primes between (Class 5)Prime factorisation (Class 6)

Prime or composite?

Class 4–5 · Worksheet 1 · set 20
Name:Date:Score:    / 16

Write prime or composite.

  1. 4 — prime or composite?
  2. 91 — prime or composite?
  3. 89 — prime or composite?
  4. 53 — prime or composite?
  5. 64 — prime or composite?
  6. 98 — prime or composite?
  7. 69 — prime or composite?
  8. 47 — prime or composite?
  9. 79 — prime or composite?
  10. 87 — prime or composite?
  11. 29 — prime or composite?
  12. 16 — prime or composite?
  13. 81 — prime or composite?
  14. 45 — prime or composite?
  15. 18 — prime or composite?
  16. 37 — prime or composite?

Primes between

Class 5 · Worksheet 2 · set 20
Name:Date:Score:    / 6

Write the prime numbers.

  1. Write the prime numbers between 20 and 30.
  2. Write the prime numbers between 40 and 50.
  3. Write the prime numbers between 10 and 20.
  4. Write the prime numbers between 70 and 80.
  5. Write the prime numbers between 90 and 100.
  6. Write the prime numbers between 30 and 40.

Prime factorisation

Class 6 · Worksheet 3 · set 20
Name:Date:Score:    / 10

Write as a product of prime numbers.

  1. Prime factorisation of 90
  2. Prime factorisation of 30
  3. Prime factorisation of 176
  4. Prime factorisation of 130
  5. Prime factorisation of 120
  6. Prime factorisation of 153
  7. Prime factorisation of 63
  8. Prime factorisation of 88
  9. Prime factorisation of 189
  10. Prime factorisation of 196

More worksheets

Questions

How many prime numbers are there between 1 and 100?

25: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97.

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