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Watch: Counting in 100s

Watch this video and learn how to count in steps of 100 using a number line and a place value chart.

Learn how to count in steps of 100 using a number line and place value chart.

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Using a number line to count in 100s

When you count up and down in hundreds, it is just like when you count in tens. Only this time, you are changing the hundreds digit. The tens and ones stay the same.

Look at this number line:

Number line from 0 to 1000, increasing in 100 at a time

Can you see how only the hundreds column is changing each time?

When you reach 1000, you begin to use the thousands column.

Remember, 1000 is the same as 10 hundreds.

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Example 1

What is three-hundred more than 231?

Three hundred is the same as three lots of 100. Use the number line to help you count up in hundreds.

Number line showing 231, 331, 431, 531.

So three-hundred more than 231 is 531.

Counting up and down in hundreds is the same as adding or subtracting hundreds.

You could also write this question as:

231 + 300 = 531

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Example 2

What is two-hundred less than 854?

Place value charts can also help you to count in hundreds. Here is 854 in a place value chart.

Place value table showing 8 hundreds, 5 tens and 4 ones

To find two hundred less, you take away two of the hundred counters in the hundreds column to find the answer.

Place value table showing 6 hundreds, 5 tens and 4 ones

Now you are left with 6 hundreds, 5 tens and 4 ones.

So the answer is 654.

As a subtraction, you would write this question:

854 鈥 200 = 654

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Example 3

A clown has 133 balloons. He buys 3 more packs of 100 balloons. How many balloons does he have now?

This question is asking you how many more balloons the clown has, so you need to count on and add.

Use the number line method and the place value method to help you answer the question. Will you get the same answer each time?

Number line method

Number line counting from 133, 233, 333, 433

Three hundred more than 133 is 433.

Place value method

You can double-check the answer using the place value method.

Place value chart showing 1 hundred, 3 tens and 3 ones

Add three more hundreds into the hundreds column:

Place value chart showing 4 hundreds, 3 tens and 3 ones

You now have 4 hundreds, 3 tens and 3 ones. That鈥檚 433 as well!

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Activity

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