What approximate value should come in place of Question mark (?) in the following equation ?
`6739 + 161 xx 4.966 - 74.99 xx 11.888 + 20% "of 121" - 10% "of 109" = ?`

Options

A. 6657
B. 7067
C. 7167
D. 6587

Answer

To solve the equation \( 6739 + 161 \times 4.966 - 74.99 \times 11.888 + 20\% \text{ of } 121 - 10\% \text{ of } 109 = ? \), we will approximate the values for easier calculation.

### Step-by-Step Solution:

1. **Approximate the Multiplications**:
- For \( 4.966 \), we can approximate it to \( 5 \).
- For \( 74.99 \), we can approximate it to \( 75 \).
- For \( 11.888 \), we can approximate it to \( 12 \).

So the equation now looks like:
\[ 6739 + 161 \times 5 - 75 \times 12 + 20\% \text{ of } 121 - 10\% \text{ of } 109 \]

2. **Calculate the Multiplications**:
- \( 161 \times 5 = 805 \)
- \( 75 \times 12 = 900 \)

Now substituting these values back into the equation:
\[ 6739 + 805 - 900 + 20\% \text{ of } 121 - 10\% \text{ of } 109 \]

3. **Calculate the Percentages**:
- \( 20\% \text{ of } 121 = \frac{20}{100} \times 121 = 24.2 \) (approximately \( 24 \))
- \( 10\% \text{ of } 109 = \frac{10}{100} \times 109 = 10.9 \) (approximately \( 11 \))

Now substituting these values back into the equation:
\[ 6739 + 805 - 900 + 24 - 11 \]

4. **Combine the Terms**:
- First, combine the positive terms:
\[ 6739 + 805 + 24 = 6568 \]
- Then combine the negative terms:
\[ 900 + 11 = 911 \]

5. **Final Calculation**:
- Now subtract the negative total from the positive total:
\[ 6568 - 911 = 5657 \]

### Final Result:
The approximate value that should come in place of the question mark (?) is:
\[ \boxed{6657} \]