Form the largest 4 - digit number using any
`4,9,8`

Answer

To form the largest 4-digit number using the digits 4, 9, and 8, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Digits**: We have the digits 4, 9, and 8 available to use.

2. **Determine the Largest Digit**: Among these digits, the largest digit is 9.

3. **Use the Largest Digit**: Since we need to form a 4-digit number and we have only three different digits, we will use the largest digit (9) more than once.

4. **Fill in the Remaining Places**: After placing 9, we need to fill the remaining three places. The next largest digit after 9 is 8, and the smallest is 4.

5. **Construct the Number**:
- Start with the largest digit: 9
- Use 9 again to maximize the number: 99
- Next, use the next largest digit: 8
- Finally, use the smallest digit: 4

6. **Final Arrangement**: Arranging these digits in descending order gives us 9984.

### Final Answer:
The largest 4-digit number that can be formed using the digits 4, 9, and 8 is **9984**.

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