Form the largest 4 - digit number using any
`7,3,0`

Answer

To form the largest 4-digit number using the digits 7, 3, and 0, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Digits**: The digits we have are 7, 3, and 0. Since we need to form a 4-digit number, we can use these digits and repeat some of them if necessary.

2. **Choose the Largest Digit**: To create the largest number, we should start with the largest digit. The largest digit among 7, 3, and 0 is 7.

3. **Form the First Digit**: Place 7 as the first digit of the 4-digit number. So, we have:
- First digit: 7

4. **Choose the Next Largest Digit**: Now we need to choose the next largest digit. The available digits are 7, 3, and 0. The next largest digit is also 7 (since we can repeat it).

5. **Form the Second Digit**: Place another 7 as the second digit. Now we have:
- First digit: 7
- Second digit: 7

6. **Choose the Next Largest Digit Again**: We still have the option to use 7 again, but we should also include the other digits to maximize the number. The next largest digit after 7 is 3.

7. **Form the Third Digit**: Place 3 as the third digit. Now we have:
- First digit: 7
- Second digit: 7
- Third digit: 3

8. **Choose the Last Digit**: Now we need one more digit. The only digit left is 0, which we will use as the last digit.

9. **Form the Fourth Digit**: Place 0 as the fourth digit. Now we have:
- First digit: 7
- Second digit: 7
- Third digit: 3
- Fourth digit: 0

10. **Final Number**: Therefore, the largest 4-digit number we can form using the digits 7, 3, and 0 is **7730**.

### Final Answer:
The largest 4-digit number formed using the digits 7, 3, and 0 is **7730**.