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 63 as a product of prime factors.
Answer: 3×3×7
- 63 = 3 × 21
- 21 = 3 × 7
- So 63 = 3 × 3 × 7 = 32 × 7
2.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
3.Use a factor tree to write 42 as a product of prime factors.
Answer: 2×3×7
- 42 = 2 × 21
- 21 = 3 × 7
- So 42 = 2 × 3 × 7
4.Which number has the prime factorisation 24 × 3?
Answer: 48
- 2 × 2 × 2 × 2 × 3 = 48
5.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
6.Use a factor tree to write 54 as a product of prime factors.
Answer: 2×3×3×3
- 54 = 2 × 27
- 27 = 3 × 9
- 9 = 3 × 3
- So 54 = 2 × 3 × 3 × 3 = 2 × 33
7.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
8.Which number has the prime factorisation 22 × 33?
Answer: 108
- 2 × 2 × 3 × 3 × 3 = 108
Marking tips
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