5th Grade Prime Factorization (Factor Trees) Worksheet — Level 3 — Practice Set 3 — Answers
Answer sheet with worked solutions for the 5th Grade factors, multiples & primes worksheet.
Success TutoringWorksheetsAnswer sheet5th Grade · Mathematics · Factors, Multiples & Primes5th 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 363 as a product of prime factors in index form.
Answer: 3×112
- 363 = 3 × 121
- 121 = 11 × 11
- So 363 = 3 × 11 × 11 = 3 × 112
2.Which number has the prime factorization 3 × 52 × 7?
Answer: 525
- 3 × 5 × 5 × 7 = 525
3.Use a factor tree to write 385 as a product of prime factors in index form.
Answer: 5×7×11
- 385 = 5 × 77
- 77 = 7 × 11
- So 385 = 5 × 7 × 11 = 5 × 7 × 11
4.Which number has the prime factorization 2 × 52 × 7?
Answer: 350
- 2 × 5 × 5 × 7 = 350
5.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
6.Which number has the prime factorization 2 × 5 × 11?
Answer: 110
- 2 × 5 × 11 = 110
7.Use a factor tree to write 70 as a product of prime factors in index form.
Answer: 2×5×7
- 70 = 2 × 35
- 35 = 5 × 7
- So 70 = 2 × 5 × 7 = 2 × 5 × 7
8.Which number has the prime factorization 33 × 7?
Answer: 189
- 3 × 3 × 3 × 7 = 189
Marking tips
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