Let's solve each problem step by step using
factor trees to find the
prime factorization of each number. We’ll follow the example given for 16, where we break down the number into factors until all are
prime numbers (circled in blue), and non-prime factors (in orange) are broken down further.
---
🔹 1. 36
We start with 36.
- 36 = 6 × 6 → but better to use smaller factors.
- Let’s split 36 as:
36 = 2 × 18 (2 is prime, so circle it)
Now break down 18:
- 18 = 2 × 9 (2 is prime)
- 9 = 3 × 3 (both 3s are prime)
So:
```
36
/ \
2 18
/ \
2 9
/ \
3 3
```
Prime factors: 2, 2, 3, 3
→
36 = 2 × 2 × 3 × 3 = 2² × 3²
✔ Answer:
36 = 2² × 3²
---
🔹 2. 54
Start with 54:
- 54 = 2 × 27 (2 is prime)
- 27 = 3 × 9 (3 is prime)
- 9 = 3 × 3 (both prime)
```
54
/ \
2 27
/ \
3 9
/ \
3 3
```
Prime factors: 2, 3, 3, 3
→
54 = 2 × 3 × 3 × 3 = 2 × 3³
✔ Answer:
54 = 2 × 3³
---
🔹 3. 135
Start with 135:
- 135 = 5 × 27 (5 is prime)
- 27 = 3 × 9 (3 is prime)
- 9 = 3 × 3
```
135
/ \
5 27
/ \
3 9
/ \
3 3
```
Prime factors: 5, 3, 3, 3
→
135 = 5 × 3 × 3 × 3 = 5 × 3³
✔ Answer:
135 = 3³ × 5
---
🔹 4. 525
Start with 525:
- 525 = 5 × 105 (5 is prime)
- 105 = 5 × 21 (5 is prime)
- 21 = 3 × 7 (both prime)
```
525
/ \
5 105
/ \
5 21
/ \
3 7
```
Prime factors: 5, 5, 3, 7
→
525 = 5 × 5 × 3 × 7 = 3 × 5² × 7
✔ Answer:
525 = 3 × 5² × 7
---
🔹 5. 693
Start with 693:
- Check divisibility:
Sum of digits: 6+9+3 = 18 → divisible by 3 → yes.
- 693 ÷ 3 = 231 → so 693 = 3 × 231
- 231 ÷ 3 = 77 → 231 = 3 × 77
- 77 = 7 × 11 (both prime)
So:
```
693
/ \
3 231
/ \
3 77
/ \
7 11
```
Prime factors: 3, 3, 7, 11
→
693 = 3 × 3 × 7 × 11 = 3² × 7 × 11
✔ Answer:
693 = 3² × 7 × 11
---
✔ Final Answers:
| Number | Prime Factorization (Product) | Exponential Form |
|--------|-------------------------------|------------------|
| 36 | 2 × 2 × 3 × 3 | 2² × 3² |
| 54 | 2 × 3 × 3 × 3 | 2 × 3³ |
| 135 | 3 × 3 × 3 × 5 | 3³ × 5 |
| 525 | 3 × 5 × 5 × 7 | 3 × 5² × 7 |
| 693 | 3 × 3 × 7 × 11 | 3² × 7 × 11 |
---
🌲 How to Fill in the Trees:
Use the key:
-
Blue circles: Prime factors
-
Orange rectangles: Not prime (need to be broken down)
#### Example: 36 Tree
```
36
/ \
2 18
/ \
2 9
/ \
3 3
```
Fill in:
- First level: 2 (blue), 18 (orange)
- Second: 2 (blue), 9 (orange)
- Third: 3 (blue), 3 (blue)
Then write:
36 = 2² × 3²
Repeat this process for others.
---
Let me know if you'd like a printable version or a visual diagram!
Parent Tip: Review the logic above to help your child master the concept of prime factorization worksheet 5th grade.