6th Grade Prime Factorization (Factor Trees) Worksheet — Level 3 — Practice Set 4 — 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 4 — 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 308 as a product of prime factors in index form.
Answer: 22×7×11
- 308 = 2 × 154
- 154 = 2 × 77
- 77 = 7 × 11
- So 308 = 2 × 2 × 7 × 11 = 22 × 7 × 11
2.Which number has the prime factorization 2 × 3 × 112?
Answer: 726
- 2 × 3 × 11 × 11 = 726
3.Use a factor tree to write 140 as a product of prime factors in index form.
Answer: 22×5×7
- 140 = 2 × 70
- 70 = 2 × 35
- 35 = 5 × 7
- So 140 = 2 × 2 × 5 × 7 = 22 × 5 × 7
4.Which number has the prime factorization 52 × 11?
Answer: 275
- 5 × 5 × 11 = 275
5.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
6.Which number has the prime factorization 2 × 5 × 11?
Answer: 110
- 2 × 5 × 11 = 110
7.Use a factor tree to write 847 as a product of prime factors in index form.
Answer: 7×112
- 847 = 7 × 121
- 121 = 11 × 11
- So 847 = 7 × 11 × 11 = 7 × 112
8.Which number has the prime factorization 5 × 7 × 11?
Answer: 385
- 5 × 7 × 11 = 385
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.