1.04 Partition 5 digit numbers

Lesson

Can you partition numbers up to the thousands (4 digits)?

Examples

Example 1

We have written a number in the number expander.

a

What is the value of the tens?

Worked Solution
Create a strategy

Use the given number expander. Add 0 as a placeholder.

Apply the idea

We can see from the number expander that we have 8 tens which is equal to 80.

b

What is the value of the hundreds?

Worked Solution
Create a strategy

Use the given number expander. Add 0 as a placeholder.

Apply the idea

We can see from the number expander that we have 9 hundreds which is equal to 900.

Idea summary

Numbers can be described using any place value such as thousands, hundreds, tens and units.

Expanded notation of 5 digit numbers

Let's see how to break up a 5 digit number, and then put it back together. We'll start with a 4 digit number to warm up.

Exploration

Enter a five digit number into the applet and drag the number tiles around to see what amount each digit represents.

Any five digit number can be expanded by their ten thousands, thousands, hundreds, tens, and units value.

Examples

Example 2

Fill in the number expander for 60\,908.

a
Worked Solution
Create a strategy

Put the given number in a place value table.

Apply the idea

So, the complete number expander is:

b

Write 60\,908 as a number sentence.

⬚+⬚+⬚

Worked Solution
Create a strategy

Use the number expander from part (a).

Apply the idea

6 ten thousands is 60\,000, 9 hundreds is 900, and 8 units is 8.

60\,908=60\,000+900+8

Example 3

Write the following as a single number: 10\,000+7000+90.

Worked Solution
Create a strategy

Put each first digit in a place value table. For the values not given, use 0 as placeholder.

Apply the idea

The place value table shows how the values add together.

10\,000+7000+90 = 17\,090

Idea summary

Except for the far left digit of our number, every place must have a number in it. If we don't have any of a place, we must put a zero in that place. The number twenty eight thousand and forty nine has no hundreds, so we would write it like this 28\,049.

Outcomes

MA2-4NA

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

MA2-5NA

uses mental and written strategies for addition and subtraction involving two-, three-, four and five-digit numbers