Year 8 Prime Factorisation (Factor Trees) Worksheet — Level 3 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 8 factors, multiples & primes worksheet.
Success TutoringWorksheetsAnswer sheetYear 8 · Mathematics · Factors, Multiples & PrimesYear 8 Prime Factorisation (Factor Trees) Worksheet — Level 3 — Practice Set 4 — 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 175 as a product of prime factors in index form.
Answer: 52×7
- 175 = 5 × 35
- 35 = 5 × 7
- So 175 = 5 × 5 × 7 = 52 × 7
2.Which number has the prime factorisation 2 × 3 × 11?
Answer: 66
- 2 × 3 × 11 = 66
3.Use a factor tree to write 588 as a product of prime factors in index form.
Answer: 22×3×72
- 588 = 2 × 294
- 294 = 2 × 147
- 147 = 3 × 49
- 49 = 7 × 7
- So 588 = 2 × 2 × 3 × 7 × 7 = 22 × 3 × 72
4.Which number has the prime factorisation 2 × 34 × 5?
Answer: 810
- 2 × 3 × 3 × 3 × 3 × 5 = 810
5.Use a factor tree to write 525 as a product of prime factors in index form.
Answer: 3×52×7
- 525 = 3 × 175
- 175 = 5 × 35
- 35 = 5 × 7
- So 525 = 3 × 5 × 5 × 7 = 3 × 52 × 7
6.Which number has the prime factorisation 3 × 5 × 72?
Answer: 735
- 3 × 5 × 7 × 7 = 735
7.Use a factor tree to write 150 as a product of prime factors in index form.
Answer: 2×3×52
- 150 = 2 × 75
- 75 = 3 × 25
- 25 = 5 × 5
- So 150 = 2 × 3 × 5 × 5 = 2 × 3 × 52
8.Which number has the prime factorisation 23 × 112?
Answer: 968
- 2 × 2 × 2 × 11 × 11 = 968
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.