Subject level: Foundation
Definition
When you round off a number to the nearest hundred, all the digits in the columns after the hundreds column must be zero.
For example 631 is to be rounded to the nearest hundred. 6 is in the hundred column, but to round to the nearest hundred, I need to look at the digit in the column to the right of the 6 - 3, in the tens column. Since 3 is less than 5, I simply discard it. So, 631 rounded to the nearest hundred is 600. For example 685 rounded to the nearest hundred is 700, since 8 is greater than 5.