5th Grade Prime Factorization (Factor Trees) Worksheet — Level 3 — Practice Set 4 — 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 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 462 as a product of prime factors in index form.
Answer: 2×3×7×11
- 462 = 2 × 231
- 231 = 3 × 77
- 77 = 7 × 11
- So 462 = 2 × 3 × 7 × 11 = 2 × 3 × 7 × 11
2.Which number has the prime factorization 23 × 72?
Answer: 392
- 2 × 2 × 2 × 7 × 7 = 392
3.Use a factor tree to write 252 as a product of prime factors in index form.
Answer: 22×32×7
- 252 = 2 × 126
- 126 = 2 × 63
- 63 = 3 × 21
- 21 = 3 × 7
- So 252 = 2 × 2 × 3 × 3 × 7 = 22 × 32 × 7
4.Which number has the prime factorization 22 × 3 × 5?
Answer: 60
- 2 × 2 × 3 × 5 = 60
5.Use a factor tree to write 330 as a product of prime factors in index form.
Answer: 2×3×5×11
- 330 = 2 × 165
- 165 = 3 × 55
- 55 = 5 × 11
- So 330 = 2 × 3 × 5 × 11 = 2 × 3 × 5 × 11
6.Which number has the prime factorization 5 × 7 × 11?
Answer: 385
- 5 × 7 × 11 = 385
7.Use a factor tree to write 660 as a product of prime factors in index form.
Answer: 22×3×5×11
- 660 = 2 × 330
- 330 = 2 × 165
- 165 = 3 × 55
- 55 = 5 × 11
- So 660 = 2 × 2 × 3 × 5 × 11 = 22 × 3 × 5 × 11
8.Which number has the prime factorization 2 × 3 × 11?
Answer: 66
- 2 × 3 × 11 = 66
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