Free · Class 4–6 · 3 worksheets · answer keys · practise online · set 23

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 23
Name:Date:Score:    / 16

Write prime or composite.

  1. 33 — prime or composite?
  2. 43 — prime or composite?
  3. 4 — prime or composite?
  4. 78 — prime or composite?
  5. 49 — prime or composite?
  6. 81 — prime or composite?
  7. 20 — prime or composite?
  8. 71 — prime or composite?
  9. 28 — prime or composite?
  10. 53 — prime or composite?
  11. 98 — prime or composite?
  12. 14 — prime or composite?
  13. 24 — prime or composite?
  14. 45 — prime or composite?
  15. 17 — prime or composite?
  16. 68 — prime or composite?

Primes between

Class 5 · Worksheet 2 · set 23
Name:Date:Score:    / 6

Write the prime numbers.

  1. Write the prime numbers between 40 and 50.
  2. Write the prime numbers between 90 and 100.
  3. Write the prime numbers between 0 and 10.
  4. Write the prime numbers between 60 and 70.
  5. Write the prime numbers between 70 and 80.
  6. Write the prime numbers between 30 and 40.

Prime factorisation

Class 6 · Worksheet 3 · set 23
Name:Date:Score:    / 10

Write as a product of prime numbers.

  1. Prime factorisation of 54
  2. Prime factorisation of 126
  3. Prime factorisation of 18
  4. Prime factorisation of 175
  5. Prime factorisation of 160
  6. Prime factorisation of 30
  7. Prime factorisation of 186
  8. Prime factorisation of 28
  9. Prime factorisation of 150
  10. Prime factorisation of 156

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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