4-Digit Numbers

Building Numbers

We already know how to group ones into tens, and tens into hundreds. To build even bigger numbers, we follow the same pattern!

We group 10 hundreds together to make 1 thousand: = $10$ hundreds = $1$ thousand =

Now our place value table needs a new column for thousands. This helps us organize and read large numbers.

This table shows we have 1 thousand, 2 hundreds, 4 tens, and 3 ones. This makes the number $1\,243$.

Definition 4-Digit Number

In the base-10 system, the place of a digit tells us its value. We can show a number like $1\,243$ in many different ways:

With digits: $$1\,243$$
In expanded form: $$\begin{aligned}[t] 1\text{ thousand }&+& 2\text{ hundreds }&+& 4\text{ tens }&+& 3\text{ ones }\\ 1\,000 &+& 200 &+& 40 &+& 3 \\ \end{aligned}$$
With words: one thousand two hundred forty-three
In a place value table:

Thousands Hundreds Tens Ones

1 2 4 3
With blocks:

A number line shows numbers in order, like a long ruler. The numbers get bigger as we move to the right.
To count big numbers faster, we can take big jumps of 10! This is called counting by tens. We say: "ten, twenty, thirty..."

Definition Number Line

A number line is a line that shows numbers in order from smallest to largest. The distance between each number is always the same.