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Watch: Counting up and down on a numberline

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Number lines are a great way to see where a number is compared to another number.

They also help you to order numbers, understand place value and estimate where a number is.

Did you know?

This video explains how to count up and down from 10,000 using a number line.

This number line shows numbers increasing in thousands up to 10,000.

A number line 0 - 10,000. A boy runs above number line at the 4,000 mark.

Charlie is completing a 10,000 m run for charity. He has run 4000 m so far.

By looking at the number line, you can see that Charlie has to run 6,000 m more in order to complete the 10,000 m run.

Here are some more examples to practise how to estimate, draw and label numbers on a number line.

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Example 1

Can you estimate what number is shown on the number line?

Number line shows 5000-10000. An arrow points half way on the line.

The arrow seems to be exactly half way between 5,000 and 10,000.

To find out what number that is, first you have to find the difference between 10,000 and 5,000.

10,000 鈥 5,000 = 5,000

Then halve it.

5,000 梅 2 = 2,500

Now you can add 2,500 to 5,000 to work out what the number in the middle is.

5,000 + 2,500 = 7,500

Number line shows 5000-10000. An arrow points half way on the line, labelled 7500.

As an estimate, the number must be around 7,500.

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Example 2

What number is being shown on this number line?

Number line 7500-10000. An arrow points on the fourth interval along the line.

First, work out what the intervals represent.

There are 10 intervals between 7,500 and 10,000. The difference between these two numbers is 2,500.

To find out what each interval is worth, work out how many tens are in 2,500.

2,500 梅 10 = 250

This means that each interval is worth 250.

You can count up in 250s to get to the arrow or work out 4 lots of 250 and add it on to 7,500. This is because the arrow is 4 intervals from the 7,500 mark.

4 x 250 = 1,000

7,500 + 1,000 = 8,500

So the number shown on the line is 8,500.

Number line 7500-10000. 8500 is marked on the line at the fourth interval
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Example 3

Could you mark 4,100 on a number line?

Number line shows 0-10,000 with intervals of 1000

4,100 is much closer to 4,000 than 5,000. You would have to draw the arrow just after 4,000!

Number line 0-10,000 with marker at each 1000 interval. An estimated 4100 is marked by an arrow.
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Activity

Quiz

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More on Rounding and estimating

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