Year 6 Prime Factorisation (Factor Trees) Worksheet — Level 2 — 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 2 — Practice Set 2 — 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 30 as a product of prime factors.
Answer: 2×3×5
- 30 = 2 × 15
- 15 = 3 × 5
- So 30 = 2 × 3 × 5
2.Use a factor tree to write 225 as a product of prime factors.
Answer: 3×3×5×5
- 225 = 3 × 75
- 75 = 3 × 25
- 25 = 5 × 5
- So 225 = 3 × 3 × 5 × 5 = 32 × 52
3.Use a factor tree to write 252 as a product of prime factors.
Answer: 2×2×3×3×7
- 252 = 2 × 126
- 126 = 2 × 63
- 63 = 3 × 21
- 21 = 3 × 7
- So 252 = 2 × 2 × 3 × 3 × 7 = 22 × 32 × 7
4.Which number has the prime factorisation 33 × 7?
Answer: 189
- 3 × 3 × 3 × 7 = 189
5.Use a factor tree to write 90 as a product of prime factors.
Answer: 2×3×3×5
- 90 = 2 × 45
- 45 = 3 × 15
- 15 = 3 × 5
- So 90 = 2 × 3 × 3 × 5 = 2 × 32 × 5
6.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
7.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
8.Which number has the prime factorisation 22 × 3 × 52?
Answer: 300
- 2 × 2 × 3 × 5 × 5 = 300
Marking tips
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