Year 6 Prime Factorisation (Factor Trees) Worksheet — Level 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 3 — 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 66 as a product of prime factors in index form.
Answer: 2×3×11
- 66 = 2 × 33
- 33 = 3 × 11
- So 66 = 2 × 3 × 11 = 2 × 3 × 11
2.Which number has the prime factorisation 2 × 3 × 11?
Answer: 66
- 2 × 3 × 11 = 66
3.Use a factor tree to write 165 as a product of prime factors in index form.
Answer: 3×5×11
- 165 = 3 × 55
- 55 = 5 × 11
- So 165 = 3 × 5 × 11 = 3 × 5 × 11
4.Which number has the prime factorisation 22 × 5 × 11?
Answer: 220
- 2 × 2 × 5 × 11 = 220
5.Use a factor tree to write 245 as a product of prime factors in index form.
Answer: 5×72
- 245 = 5 × 49
- 49 = 7 × 7
- So 245 = 5 × 7 × 7 = 5 × 72
6.Which number has the prime factorisation 2 × 32 × 11?
Answer: 198
- 2 × 3 × 3 × 11 = 198
7.Use a factor tree to write 135 as a product of prime factors in index form.
Answer: 33×5
- 135 = 3 × 45
- 45 = 3 × 15
- 15 = 3 × 5
- So 135 = 3 × 3 × 3 × 5 = 33 × 5
8.Which number has the prime factorisation 3 × 5 × 11?
Answer: 165
- 3 × 5 × 11 = 165
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