Write the set of odd factors of 72.

Answer

To find the set of odd factors of 72, we can follow these steps:

### Step 1: Find the factors of 72
To find the factors of 72, we need to identify all pairs of numbers that multiply to give 72. We can start by dividing 72 by integers starting from 1.

- 1 × 72 = 72
- 2 × 36 = 72
- 3 × 24 = 72
- 4 × 18 = 72
- 6 × 12 = 72
- 8 × 9 = 72

From this, we can list all the factors of 72:
**Factors of 72:** 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72

### Step 2: Identify the odd factors
Next, we need to filter out the odd factors from the list we obtained. Odd numbers are those that are not divisible by 2.

From the factors of 72, we can identify the odd ones:
- 1 (odd)
- 2 (even)
- 3 (odd)
- 4 (even)
- 6 (even)
- 8 (even)
- 9 (odd)
- 12 (even)
- 18 (even)
- 24 (even)
- 36 (even)
- 72 (even)

The odd factors are:
**Odd Factors of 72:** 1, 3, 9

### Step 3: Write the set of odd factors
Finally, we can write the set of odd factors of 72 in set notation:
**Set of Odd Factors of 72:** {1, 3, 9}

### Final Answer
The set of odd factors of 72 is {1, 3, 9}.

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