For every question, four probable answers bear in letters (A), (B), (C) and (D) are given. Only one out of these is correct. You have to choose the correct answer.
The greatest number formed by using the digits 1, 3, 0, 9, 7 when one digit is used only once is

Options

A. 10379
B. 97310
C. 99731
D. 79031

Answer

To find the greatest number that can be formed using the digits 1, 3, 0, 9, and 7, we will follow these steps:

### Step-by-Step Solution:

1. **List the Digits**: The digits we have are 1, 3, 0, 9, and 7.

2. **Identify the Largest Digit**: To form the greatest number, we should start with the largest digit. Here, the largest digit is 9.

3. **Arrange the Remaining Digits**: After 9, we need to arrange the remaining digits in descending order. The remaining digits are 1, 3, 0, and 7. The largest among these is 7.

4. **Continue Arranging**: Next, we take the next largest digit, which is 3. After 3, we have 1 and 0 left. The next largest is 1.

5. **Final Digit**: The last digit will be 0, as it is the smallest.

6. **Combine the Digits**: Now, we combine the digits in the order we have arranged them: 9, 7, 3, 1, 0.

7. **Write the Final Answer**: Therefore, the greatest number formed by using the digits 1, 3, 0, 9, and 7 is **97310**.

### Answer:
The greatest number formed is **97310**.

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