Form the greatest and smallest 5-digit number in each of the following by repeating any one of the digits. Also, use each digit in the number at least once.
`5, 0, 8`

Answer

To solve the problem of forming the greatest and smallest 5-digit numbers using the digits 5, 0, and 8, while repeating one digit and ensuring each digit is used at least once, we can follow these steps:

### Step 1: Identify the digits available
The digits we have are 5, 0, and 8.

### Step 2: Form the smallest 5-digit number
1. **Arrange the digits in ascending order**: The order is 0, 5, 8.
2. **Ensure the number is a 5-digit number**: Since a 5-digit number cannot start with 0, we will use 5 as the leading digit.
3. **Repeat the smallest digit (0)**: To form the smallest number, we will repeat 0.
4. **Construct the number**: The smallest 5-digit number will be 50008.

### Step 3: Form the greatest 5-digit number
1. **Arrange the digits in descending order**: The order is 8, 5, 0.
2. **Repeat the largest digit (8)**: To form the greatest number, we will repeat 8.
3. **Construct the number**: The greatest 5-digit number will be 88850.

### Final Answers
- **Smallest 5-digit number**: 50008
- **Greatest 5-digit number**: 88850

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