To round a number to the nearest 100, check the tens digit to decide whether to round up or round down. 

If the tens and ones are 50 or more, round up.

If they are 49 or less, round down.

Example => 4149 to the nearest 100 is 4100, but 4150 to the nearest hundred is 4200. To round a number to the nearest 1000, check the hundreds digit to decide whether to round up or round down. If the hundreds, tens and ones are 500 or more, round up. If they are 499 or less, round down.

Example => 16,500 to the nearest 1000 is 17,000, but 16,499 to the nearest thousand is 16,000.

Now try a few practice questions!