Year 6 Prime Factorisation (Factor Trees) Worksheet — Level 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 — 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 105 as a product of prime factors.
Answer: 3×5×7
- 105 = 3 × 35
- 35 = 5 × 7
- So 105 = 3 × 5 × 7
2.Use a factor tree to write 270 as a product of prime factors.
Answer: 2×3×3×3×5
- 270 = 2 × 135
- 135 = 3 × 45
- 45 = 3 × 15
- 15 = 3 × 5
- So 270 = 2 × 3 × 3 × 3 × 5 = 2 × 33 × 5
3.Use a factor tree to write 168 as a product of prime factors.
Answer: 2×2×2×3×7
- 168 = 2 × 84
- 84 = 2 × 42
- 42 = 2 × 21
- 21 = 3 × 7
- So 168 = 2 × 2 × 2 × 3 × 7 = 23 × 3 × 7
4.Which number has the prime factorisation 33 × 7?
Answer: 189
- 3 × 3 × 3 × 7 = 189
5.Use a factor tree to write 40 as a product of prime factors.
Answer: 2×2×2×5
- 40 = 2 × 20
- 20 = 2 × 10
- 10 = 2 × 5
- So 40 = 2 × 2 × 2 × 5 = 23 × 5
6.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
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 2 × 32 × 7?
Answer: 126
- 2 × 3 × 3 × 7 = 126
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