Free · Class 4–6 · 3 worksheets · answer keys · practise online · set 15

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 15
Name:Date:Score:    / 16

Write prime or composite.

  1. 28 — prime or composite?
  2. 59 — prime or composite?
  3. 62 — prime or composite?
  4. 95 — prime or composite?
  5. 77 — prime or composite?
  6. 89 — prime or composite?
  7. 23 — prime or composite?
  8. 53 — prime or composite?
  9. 9 — prime or composite?
  10. 99 — prime or composite?
  11. 61 — prime or composite?
  12. 69 — prime or composite?
  13. 17 — prime or composite?
  14. 8 — prime or composite?
  15. 90 — prime or composite?
  16. 19 — prime or composite?

Primes between

Class 5 · Worksheet 2 · set 15
Name:Date:Score:    / 6

Write the prime numbers.

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

Prime factorisation

Class 6 · Worksheet 3 · set 15
Name:Date:Score:    / 10

Write as a product of prime numbers.

  1. Prime factorisation of 70
  2. Prime factorisation of 126
  3. Prime factorisation of 189
  4. Prime factorisation of 28
  5. Prime factorisation of 174
  6. Prime factorisation of 165
  7. Prime factorisation of 188
  8. Prime factorisation of 110
  9. Prime factorisation of 45
  10. Prime factorisation of 164

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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