Express the following as the sum of two odd primes.
18

Answer

To express 18 as the sum of two odd prime numbers, we can follow these steps:

### Step 1: Identify Odd Prime Numbers Less Than 18
First, we need to list the odd prime numbers that are less than 18. The odd prime numbers are:
- 3
- 5
- 7
- 11
- 13
- 17

### Step 2: Find Combinations of Two Odd Primes
Next, we will check combinations of these odd primes to see which pairs add up to 18.

1. **3 + 15** (15 is not prime)
2. **5 + 13** (13 is prime)
3. **7 + 11** (11 is prime)
4. **11 + 7** (already counted)
5. **13 + 5** (already counted)
6. **17 + 1** (1 is not prime)

From this, we find two pairs that sum to 18:
- 5 + 13
- 7 + 11

### Step 3: Write the Final Answer
Thus, we can express 18 as the sum of two odd primes in two different ways:
- 18 = 5 + 13
- 18 = 7 + 11

### Final Answer
The answer is:
- 18 can be expressed as the sum of two odd primes: 5 + 13 or 7 + 11.

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