First, identify the digit in the hundreds place.
12,781
Left 1 - ten-thousands place
2 - thousands place
<em>7 - hundreds place - </em>the one we are interested in
8 - tens place
Right 1 - ones place
Now we know the 7 is in the hundreds place.
12,781
To round off to the nearest 100, all digits to the right of the digit in the hundreds place become zero.
12,781 becomes first 12,700, but now we need one more step.
Look in the original number at the digit just to the right of the hundreds digit. It is an 8. Since 8 is greater than or equal to 5, the previous digit goes up by 1, so the 7 becomes an 8, as in 12,800, and the rounded number is 12,800.
Answer: 12,800
