Year 5 Prime Factorisation (Factor Trees) Worksheet — Level 3 — Practice Set 2 — Answers
Answer sheet with worked solutions for the Year 5 factors, multiples & primes worksheet.
Success TutoringWorksheetsAnswer sheetYear 5 · Mathematics · Factors, Multiples & PrimesYear 5 Prime Factorisation (Factor Trees) Worksheet — Level 3 — Practice Set 2 — Answers
Keep splitting each number into two factors until every branch ends in a prime. Write repeated factors with an index, e.g. 2 × 2 × 2 = 23.
1.Use a factor tree to write 300 as a product of prime factors in index form.
Answer: 22×3×52
- 300 = 2 × 150
- 150 = 2 × 75
- 75 = 3 × 25
- 25 = 5 × 5
- So 300 = 2 × 2 × 3 × 5 × 5 = 22 × 3 × 52
2.Which number has the prime factorisation 2 × 5 × 11?
Answer: 110
- 2 × 5 × 11 = 110
3.Use a factor tree to write 594 as a product of prime factors in index form.
Answer: 2×33×11
- 594 = 2 × 297
- 297 = 3 × 99
- 99 = 3 × 33
- 33 = 3 × 11
- So 594 = 2 × 3 × 3 × 3 × 11 = 2 × 33 × 11
4.Which number has the prime factorisation 2 × 112?
Answer: 242
- 2 × 11 × 11 = 242
5.Use a factor tree to write 250 as a product of prime factors in index form.
Answer: 2×53
- 250 = 2 × 125
- 125 = 5 × 25
- 25 = 5 × 5
- So 250 = 2 × 5 × 5 × 5 = 2 × 53
6.Which number has the prime factorisation 22 × 3 × 5 × 11?
Answer: 660
- 2 × 2 × 3 × 5 × 11 = 660
7.Use a factor tree to write 726 as a product of prime factors in index form.
Answer: 2×3×112
- 726 = 2 × 363
- 363 = 3 × 121
- 121 = 11 × 11
- So 726 = 2 × 3 × 11 × 11 = 2 × 3 × 112
8.Which number has the prime factorisation 22 × 3 × 5?
Answer: 60
- 2 × 2 × 3 × 5 = 60
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
- For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
- Celebrate what went well first, then pick one thing to work on next.