Round numbers to the nearest 10, 100 and 1000
Learn about rounding numbers up or down to the nearest 10, 100 or 1000.
This lesson includes:
- a catch-up quiz
- a learning summary
- two videos
- two activities
To get started, let's see how well you know this topic already. Take the catch-up quiz below to find out.
Learn about rounding numbers to the nearest 10, 100 or 1000 with Albert and his jars of sweets!
The rule for rounding
Always look at the digit to the right of the one you’re supposed to be rounding to:
- if it is 5 or more, then round it up
- if it is less than 5, then round it down
To round a number to the nearest 10, look at the amount of ones. If this is 5 or more, round up. If it is 4 or less, round down.
Round 1289 to the nearest ten.
First, look at the ones digit:
9 is greater than 5, so you round up.
So 1289 rounded to the nearest ten is 1290.
The number line below also shows you how much closer 1289 is to 1290.
To round a number to the nearest 100, look at the tens digit. If the tens digit is 5 or more, round up. If the tens digit is 4 or less, round down.
Round 2233 to the nearest hundred.
Look at the tens digit:
3 is less than 5, so you round down.
2233 rounded to the nearest hundred is 2200.
To round a number to the nearest 1000, look at the hundreds digit. If the hundreds digit is 5 or more, round up. If the hundreds digit is 4 or less, round down.
Round 5432 to the nearest thousand.
Remember to look at the hundreds digit:
4 is in the hundreds column, so you round down.
5432 rounded to the nearest thousand is 5000.
Even when numbers get larger, you can still apply the same rules to round - just look at the digit to the right of the value you are rounding to!
Follow this BBC Supermovers video with Laura Bubble to find out more about rounding numbers up and down!
Now you've found out more about rounding numbers, try this activity. Round the numbers to the nearest 10 by replacing the labels.
Now see if you can round these numbers to the nearest 10... then round up numbers to the nearest 100!
Play Guardians: Defenders of Mathematica to learn more and sharpen your skills on this topic.
There's more to learn
Have a look at these other resources.