Year 6 Prime Factorisation (Factor Trees) Worksheet — Level 3 — Practice Set 2 — Answers
Answer sheet with worked solutions for the Year 6 factors, multiples & primes worksheet.
Success TutoringWorksheetsAnswer sheetYear 6 · Mathematics · Factors, Multiples & PrimesYear 6 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 770 as a product of prime factors in index form.
Answer: 2×5×7×11
- 770 = 2 × 385
- 385 = 5 × 77
- 77 = 7 × 11
- So 770 = 2 × 5 × 7 × 11 = 2 × 5 × 7 × 11
2.Which number has the prime factorisation 23 × 32 × 11?
Answer: 792
- 2 × 2 × 2 × 3 × 3 × 11 = 792
3.Use a factor tree to write 242 as a product of prime factors in index form.
Answer: 2×112
- 242 = 2 × 121
- 121 = 11 × 11
- So 242 = 2 × 11 × 11 = 2 × 112
4.Which number has the prime factorisation 22 × 52 × 7?
Answer: 700
- 2 × 2 × 5 × 5 × 7 = 700
5.Use a factor tree to write 270 as a product of prime factors in index form.
Answer: 2×33×5
- 270 = 2 × 135
- 135 = 3 × 45
- 45 = 3 × 15
- 15 = 3 × 5
- So 270 = 2 × 3 × 3 × 3 × 5 = 2 × 33 × 5
6.Which number has the prime factorisation 5 × 112?
Answer: 605
- 5 × 11 × 11 = 605
7.Use a factor tree to write 330 as a product of prime factors in index form.
Answer: 2×3×5×11
- 330 = 2 × 165
- 165 = 3 × 55
- 55 = 5 × 11
- So 330 = 2 × 3 × 5 × 11 = 2 × 3 × 5 × 11
8.Which number has the prime factorisation 3 × 7 × 11?
Answer: 231
- 3 × 7 × 11 = 231
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.