Year 6 Prime Factorisation (Factor Trees) Worksheet — Level 2 — Practice Set 3 — 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 3 — 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 72 as a product of prime factors.
Answer: 2×2×2×3×3
- 72 = 2 × 36
- 36 = 2 × 18
- 18 = 2 × 9
- 9 = 3 × 3
- So 72 = 2 × 2 × 2 × 3 × 3 = 23 × 32
2.Use a factor tree to write 294 as a product of prime factors.
Answer: 2×3×7×7
- 294 = 2 × 147
- 147 = 3 × 49
- 49 = 7 × 7
- So 294 = 2 × 3 × 7 × 7 = 2 × 3 × 72
3.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
4.Which number has the prime factorisation 22 × 5 × 7?
Answer: 140
- 2 × 2 × 5 × 7 = 140
5.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
6.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
7.Use a factor tree to write 36 as a product of prime factors.
Answer: 2×2×3×3
- 36 = 2 × 18
- 18 = 2 × 9
- 9 = 3 × 3
- So 36 = 2 × 2 × 3 × 3 = 22 × 32
8.Which number has the prime factorisation 2 × 3 × 7?
Answer: 42
- 2 × 3 × 7 = 42
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