Topics
2. Forwards and backwards
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AustraliaNSW
Stage 2

2.02 Count by 10's, 100's

Lesson
Practice
Lesson

Are you ready?

Do you remember the  names for each place in a number  , up to the thousands?

Idea summary
A name for each place value from ones to thousands. Ask your teacher for more information.

Count by 10's

Let's see how we can count by 10's, using a 100 grid.

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Examples

Example 1

Complete the pattern by adding 10 each time.

20,⬚,40, ⬚, ⬚

Worked Solution
Create a strategy

Use the place value table to add 10 to each number.

Apply the idea

Put 20 in the place value table and add 10.

TensOnes
20
+10
Result30

The amount in the tens place goes up by one and we get a result of\,30. The ones value does not change. We add ten again to complete the pattern by adding 1 to the tens place each time.

The complete pattern is 20,\,30,\,40,\,50,\,60.

Count by 100's

Now it's time to count by 100's.

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Examples

Example 2

Complete the pattern by adding 100 each time.

9,109,⬚,⬚, ⬚, 509

Worked Solution
Create a strategy

Use the place value table to add 100 to each number.

Apply the idea

Put 109 in the place value table and add 100.

HundredsTensOnes
109
+100
Result209

The amount in the hundreds place goes up by one and we get a result of\,209. The ones and tens values do not change. We add 100 again to complete the pattern by adding 1 to the hundreds place each time.

The complete pattern is 9,\,109,\,209,\,309,\,409,\,509.

Idea summary
A pattern of numbers that go up by 10. Ask your teacher for more information.
A pattern of numbers that go up by 100. Ask your teacher for more information.

Outcomes

MA2-4NA

applies place value to order, read and represent numbers of up to five digits

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