5th Grade Prime Factorization (Factor Trees) Worksheet — Level 2 — 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 2 — Answers
Keep splitting each number into two factors until every branch ends in a prime. Write the primes from smallest to largest.
1.Use a factor tree to write 70 as a product of prime factors.
Answer: 2×5×7
- 70 = 2 × 35
- 35 = 5 × 7
- So 70 = 2 × 5 × 7
2.Use a factor tree to write 270 as a product of prime factors.
Answer: 2×3×3×3×5
- 270 = 2 × 135
- 135 = 3 × 45
- 45 = 3 × 15
- 15 = 3 × 5
- So 270 = 2 × 3 × 3 × 3 × 5 = 2 × 33 × 5
3.Use a factor tree to write 162 as a product of prime factors.
Answer: 2×3×3×3×3
- 162 = 2 × 81
- 81 = 3 × 27
- 27 = 3 × 9
- 9 = 3 × 3
- So 162 = 2 × 3 × 3 × 3 × 3 = 2 × 34
4.Which number has the prime factorization 23 × 7?
Answer: 56
- 2 × 2 × 2 × 7 = 56
5.Use a factor tree to write 30 as a product of prime factors.
Answer: 2×3×5
- 30 = 2 × 15
- 15 = 3 × 5
- So 30 = 2 × 3 × 5
6.Use a factor tree to write 60 as a product of prime factors.
Answer: 2×2×3×5
- 60 = 2 × 30
- 30 = 2 × 15
- 15 = 3 × 5
- So 60 = 2 × 2 × 3 × 5 = 22 × 3 × 5
7.Use a factor tree to write 42 as a product of prime factors.
Answer: 2×3×7
- 42 = 2 × 21
- 21 = 3 × 7
- So 42 = 2 × 3 × 7
8.Which number has the prime factorization 3 × 72?
Answer: 147
- 3 × 7 × 7 = 147
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