To round, find the digit in the place you are rounding to and look at the digit just to its right. If that digit is 5 or more, round up. If it is 4 or less, round down. Every digit after the rounding place becomes zero.
Rounding is the basis of estimation. Students who can round quickly can check whether an exact answer is reasonable, which catches many errors in multi-digit work.
Questions
Does 5 round up or down?
In school math, 5 rounds up. 45 rounded to the nearest ten is 50, and 250 rounded to the nearest hundred is 300.
What happens when rounding up makes a new place?
The number simply gets another digit. 962 rounded to the nearest hundred is 1,000.