To estimate the product of 403 x 581 by rounding to the nearest hundred, we first round each number.
- 403 rounds to 400 (since it is closer to 400 than to 500).
- 581 rounds to 600 (since it is closer to 600 than to 500).
Now we multiply the rounded numbers:
\[ 400 \times 600 = 240,000 \]
Thus, the estimated product of 403 x 581 by rounding to the nearest hundred is 240,000.