Let's solve each factor tree step by step and fill in the missing numbers. The goal is to break down each number into its
prime factors using a factor tree, with
prime numbers placed in the circles. Then, write the
prime factorization as a product.
---
1) 15
- 15 = 3 × 5 (both prime)
- So:
- Left circle:
3
- Right circle:
5
- Prime factorization:
15 = 3 × 5
---
2) 14
- 14 = 2 × 7 (both prime)
- So:
- Left circle:
2
- Right circle:
7
- Prime factorization:
14 = 2 × 7
---
3) 33
- 33 = 3 × 11 (both prime)
- So:
- Left circle:
3
- Right circle:
11
- Prime factorization:
33 = 3 × 11
---
4) 12
Given:
- 12 splits into 6 and another number.
- Since 12 = 2 × 6 → so left circle =
2
- Now, 6 = 2 × 3
- So:
- Bottom left of 6:
2
- Bottom right of 6:
3
- Prime factorization:
12 = 2 × 2 × 3 or
2² × 3
---
5) 30
Given:
- 30 splits into ? and 15
- 30 = 2 × 15 → so left circle =
2
- 15 = 3 × 5 → both prime
- So:
- Bottom left of 15:
3
- Bottom right of 15:
5
- Prime factorization:
30 = 2 × 3 × 5
---
6) 27
Given:
- 27 splits into ? and 9
- 27 = 3 × 9 → so left circle =
3
- 9 = 3 × 3 → both prime
- So:
- Bottom left of 9:
3
- Bottom right of 9:
3
- Prime factorization:
27 = 3 × 3 × 3 or
3³
---
7) 20
Given:
- 20 splits into ? and ?
- Let’s split 20 = 2 × 10 → so one circle =
2, other =
10
- Now, 10 = 2 × 5
- So:
- Bottom left of 10:
2
- Bottom right of 10:
5
- Prime factorization:
20 = 2 × 2 × 5 or
2² × 5
---
8) 28
Given:
- 28 splits into ? and ?
- 28 = 2 × 14 → so one circle =
2, other =
14
- 14 = 2 × 7
- So:
- Bottom left of 14:
2
- Bottom right of 14:
7
- Prime factorization:
28 = 2 × 2 × 7 or
2² × 7
---
9) 45
Given:
- 45 splits into ? and ?
- 45 = 5 × 9 → so one circle =
5, other =
9
- 9 = 3 × 3
- So:
- Bottom left of 9:
3
- Bottom right of 9:
3
- Prime factorization:
45 = 5 × 3 × 3 or
3² × 5
---
✔ Final Answers:
| Problem | Factor Tree | Prime Factorization |
|--------|-------------|---------------------|
| 1) 15 | 3, 5 | 15 =
3 × 5 |
| 2) 14 | 2, 7 | 14 =
2 × 7 |
| 3) 33 | 3, 11 | 33 =
3 × 11 |
| 4) 12 | 2, then 2 and 3 | 12 =
2 × 2 × 3 |
| 5) 30 | 2, then 3 and 5 | 30 =
2 × 3 × 5 |
| 6) 27 | 3, then 3 and 3 | 27 =
3 × 3 × 3 |
| 7) 20 | 2, then 2 and 5 | 20 =
2 × 2 × 5 |
| 8) 28 | 2, then 2 and 7 | 28 =
2 × 2 × 7 |
| 9) 45 | 5, then 3 and 3 | 45 =
3 × 3 × 5 |
---
🔍 Explanation Summary:
- A
factor tree breaks a number down into two factors at each step until only
prime numbers remain.
-
Prime numbers are numbers greater than 1 that have no divisors other than 1 and themselves (e.g., 2, 3, 5, 7, 11, etc.).
- We always stop when all the branches end in primes.
- The final answer is the
product of all the prime numbers in the circles.
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Parent Tip: Review the logic above to help your child master the concept of 6th grade factor tree worksheet on math.