Which of the following options is incorrect ?

Options

A. Roman numeral for the largest 3 - digit number is CMXCIX
B. The smallest 4-digit number formed by using the digits 5,6,0,9 (using each digit only once ) is 5069 .
C. Estimated product of 5034 and 295 is 1500000.
D. Place value and face value are always equal at tens place .

Explanation

To solve the question "Which of the following options is incorrect?", we will analyze each option step by step.

### Step-by-Step Solution:

1. **Option 1: Roman numeral for the greatest 3-digit number is Cmxcix.**
- The greatest 3-digit number is 999.
- In Roman numerals, 999 is represented as:
- 1000 (M) - 100 (C) = 900 (CM)
- 90 is represented as 100 (C) - 10 (X) = 90 (XC)
- 9 is represented as 10 (X) - 1 (I) = 9 (IX)
- Therefore, 999 in Roman numerals is MCMXCIX, not Cmxcix.
- **Conclusion:** This option is incorrect.

2. **Option 2: The smallest 4-digit number formed by using the digits 5, 6, 0, and 9 is 5069.**
- The digits are 5, 6, 0, and 9.
- To form the smallest 4-digit number, we cannot start with 0.
- The smallest arrangement is 5069.
- **Conclusion:** This option is correct.

3. **Option 3: Estimated product of 5034 and 295 is.**
- Round off 5034 to 5000 (since 34 is less than 50).
- Round off 295 to 300 (since 95 is greater than 50).
- Now calculate the product: 5000 × 300 = 1500000.
- **Conclusion:** This option is correct.

4. **Option 4: Place value and face value are always equal at the 10th place.**
- The place value of a digit is its value based on its position in the number.
- The face value of a digit is the digit itself.
- For example, in the number 56:
- The digit 5 has a place value of 50 (5 × 10) and a face value of 5.
- Therefore, the face value and place value are not equal at the 10th place.
- **Conclusion:** This option is incorrect.

### Final Conclusion:
The incorrect option is **Option 1**: "Roman numeral for the greatest 3-digit number is Cmxcix."

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