Year 6 Prime Factorisation (Factor Trees) Worksheet — Level 2 — Practice Set 4 — 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 2 — Practice Set 4 — Answers
Keep splitting each number into two factors until every branch ends in a prime. Write the primes from smallest to largest.
1.Use a factor tree to write 147 as a product of prime factors.
Answer: 3×7×7
- 147 = 3 × 49
- 49 = 7 × 7
- So 147 = 3 × 7 × 7 = 3 × 72
2.Use a factor tree to write 30 as a product of prime factors.
Answer: 2×3×5
- 30 = 2 × 15
- 15 = 3 × 5
- So 30 = 2 × 3 × 5
3.Use a factor tree to write 140 as a product of prime factors.
Answer: 2×2×5×7
- 140 = 2 × 70
- 70 = 2 × 35
- 35 = 5 × 7
- So 140 = 2 × 2 × 5 × 7 = 22 × 5 × 7
4.Which number has the prime factorisation 2 × 3 × 5 × 7?
Answer: 210
- 2 × 3 × 5 × 7 = 210
5.Use a factor tree to write 245 as a product of prime factors.
Answer: 5×7×7
- 245 = 5 × 49
- 49 = 7 × 7
- So 245 = 5 × 7 × 7 = 5 × 72
6.Use a factor tree to write 210 as a product of prime factors.
Answer: 2×3×5×7
- 210 = 2 × 105
- 105 = 3 × 35
- 35 = 5 × 7
- So 210 = 2 × 3 × 5 × 7
7.Use a factor tree to write 162 as a product of prime factors.
Answer: 2×3×3×3×3
- 162 = 2 × 81
- 81 = 3 × 27
- 27 = 3 × 9
- 9 = 3 × 3
- So 162 = 2 × 3 × 3 × 3 × 3 = 2 × 34
8.Which number has the prime factorisation 22 × 3 × 52?
Answer: 300
- 2 × 2 × 3 × 5 × 5 = 300
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.