How many five-digit numbers can be made having exactly two identical digits?

Explanation

To solve the problem of how many five-digit numbers can be made having exactly two identical digits, we can break the solution down into clear steps.

### Step-by-Step Solution

1. **Understanding the Structure of the Number**:
- A five-digit number cannot start with 0. Therefore, the first digit must be from the set {1, 2, 3, 4, 5, 6, 7, 8, 9}.

2. **Case 1: The Identical Digits are the First Digit**:
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