6th Grade Prime Factorization (Factor Trees) Worksheet — Level 3 — Practice Set 3 — Answers
Answer sheet with worked solutions for the 6th Grade factors, multiples & primes worksheet.
Success TutoringWorksheetsAnswer sheet6th Grade · Mathematics · Factors, Multiples & Primes6th Grade Prime Factorization (Factor Trees) Worksheet — Level 3 — Practice Set 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 110 as a product of prime factors in index form.
Answer: 2×5×11
- 110 = 2 × 55
- 55 = 5 × 11
- So 110 = 2 × 5 × 11 = 2 × 5 × 11
2.Which number has the prime factorization 2 × 3 × 5 × 7?
Answer: 210
- 2 × 3 × 5 × 7 = 210
3.Use a factor tree to write 90 as a product of prime factors in index form.
Answer: 2×32×5
- 90 = 2 × 45
- 45 = 3 × 15
- 15 = 3 × 5
- So 90 = 2 × 3 × 3 × 5 = 2 × 32 × 5
4.Which number has the prime factorization 22 × 3 × 5 × 7?
Answer: 420
- 2 × 2 × 3 × 5 × 7 = 420
5.Use a factor tree to write 210 as a product of prime factors in index form.
Answer: 2×3×5×7
- 210 = 2 × 105
- 105 = 3 × 35
- 35 = 5 × 7
- So 210 = 2 × 3 × 5 × 7 = 2 × 3 × 5 × 7
6.Which number has the prime factorization 3 × 52 × 11?
Answer: 825
- 3 × 5 × 5 × 11 = 825
7.Use a factor tree to write 539 as a product of prime factors in index form.
Answer: 72×11
- 539 = 7 × 77
- 77 = 7 × 11
- So 539 = 7 × 7 × 11 = 72 × 11
8.Which number has the prime factorization 24 × 11?
Answer: 176
- 2 × 2 × 2 × 2 × 11 = 176
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
- For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
- Celebrate what went well first, then pick one thing to work on next.