Rounding numbers

When you do not need to speak or write about exact quantities or measures, learning to round numbers to 10, 100 or 1,000 can be useful.

It can make calculations easier and it also helps when you are estimating a number or quantity.

Complete this interactive activity to understand how to round numbers. Then put your knowledge to the test.

You can use a number line to help work out whether to round a number up or down.

Let's look at rounding 44 to the nearest 10.

First put 44 on the number line, then add the closest multiples of ten.

40 and 50 are the closest multiples of ten to 44.

44 is 4 away from 40 and 6 away from 50.

44 is closer to 40 and so it is rounded down to 40.

When numbers have a 5 in the ones column, you always round up to the highest ten.

Rounding to 100 and 1,000

When rounding to the nearest 100, numbers with 50 in the tens column are rounded up to the next hundred.

For example, 450 would round up to 500. Numbers below 50 are rounded down.

When rounding to the nearest 1,000, numbers with 500 in the hundreds column are rounded up to the next thousand.

For example, 1,500 would round up to 2,000. Numbers below 500 are rounded down.