7th Grade Prime Factorization (Factor Trees) Worksheet — Level 2 — Practice Set 4 — Answers
Answer sheet with worked solutions for the 7th Grade factors, multiples & primes worksheet.
Success TutoringWorksheetsAnswer sheet7th Grade · Mathematics · Factors, Multiples & Primes7th Grade Prime Factorization (Factor Trees) Worksheet — Level 2 — Practice Set 4 — 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 150 as a product of prime factors.
Answer: 2×3×5×5
- 150 = 2 × 75
- 75 = 3 × 25
- 25 = 5 × 5
- So 150 = 2 × 3 × 5 × 5 = 2 × 3 × 52
2.Use a factor tree to write 196 as a product of prime factors.
Answer: 2×2×7×7
- 196 = 2 × 98
- 98 = 2 × 49
- 49 = 7 × 7
- So 196 = 2 × 2 × 7 × 7 = 22 × 72
3.Use a factor tree to write 200 as a product of prime factors.
Answer: 2×2×2×5×5
- 200 = 2 × 100
- 100 = 2 × 50
- 50 = 2 × 25
- 25 = 5 × 5
- So 200 = 2 × 2 × 2 × 5 × 5 = 23 × 52
4.Which number has the prime factorization 2 × 3 × 5 × 7?
Answer: 210
- 2 × 3 × 5 × 7 = 210
5.Use a factor tree to write 300 as a product of prime factors.
Answer: 2×2×3×5×5
- 300 = 2 × 150
- 150 = 2 × 75
- 75 = 3 × 25
- 25 = 5 × 5
- So 300 = 2 × 2 × 3 × 5 × 5 = 22 × 3 × 52
6.Use a factor tree to write 280 as a product of prime factors.
Answer: 2×2×2×5×7
- 280 = 2 × 140
- 140 = 2 × 70
- 70 = 2 × 35
- 35 = 5 × 7
- So 280 = 2 × 2 × 2 × 5 × 7 = 23 × 5 × 7
7.Use a factor tree to write 252 as a product of prime factors.
Answer: 2×2×3×3×7
- 252 = 2 × 126
- 126 = 2 × 63
- 63 = 3 × 21
- 21 = 3 × 7
- So 252 = 2 × 2 × 3 × 3 × 7 = 22 × 32 × 7
8.Which number has the prime factorization 22 × 32 × 7?
Answer: 252
- 2 × 2 × 3 × 3 × 7 = 252
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