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.
 

Example 1

Round 1289 to the nearest ten.

First, look at the ones digit:

1289

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.

Example 2

Round 2233 to the nearest hundred.

Look at the tens digit:

2233

3 is less than 5, so you round down. 

2233 rounded to the nearest hundred id 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.

Example 3

Round 5432 to the nearest thousand.

Remember to look at the hundreds digit:

5532

4 is in the hundreds column, so you round down. 

5432 rounded to the nearest thousand is 5000.

Word problem

Jenny has 1546 marbles.

How many marbles does she have rounded to the nearest 10?

Remember to look at the ones column.

6 is more than 5, so we round up.

1550

How many marbles does she have rounded to the nearest 100?

Remember to look at the tens column.

4 is less than 5, so we round down.

1500

How many marbles does she have rounded to the nearest 1000?

Remember to look at the hundreds column.

5 -  so we round up.

2000

Answer the following questions in your workbooks.

1. A supermarket sells 187 cartons of yoghurt a week. How many cartons is this to the nearest 10 and 100?
2. There are 5245 spectators at a football match. How many is this to the nearest 10, 100 and 1000?
3. There are 2876 adult tickets and 1356 children tickets sold for a concert. To the nearest 10 and 100, how many tickets are sold altogether?
4. A shop has 2349 tins of tomatoes in stock. It sells 782 in a week. To the nearest 10, how many will be left?