Identifying Hundreds, Tens, and Ones

Every number you write is really a short code for how many hundreds, tens, and ones it contains. Once you can identify which digit sits in the hundreds place, which sits in the tens place, and which sits in the ones place, you can read, compare, and work with any number up to 999 with confidence. This skill is the foundation for later topics like expanded form and regrouping place values.

A place value chart has three columns for numbers up to 999: hundreds, tens, and ones. The digit farthest to the right always tells you the number of ones. Moving one spot to the left tells you the number of tens, and one more spot to the left tells you the number of hundreds.

Reading the chart above, the digit 3 is in the hundreds place, the digit 5 is in the tens place, and the digit 6 is in the ones place. So 356 means 3 hundreds, 5 tens, and 6 ones. You can also write this as \( 300 + 50 + 6 = 356 \).

Base ten blocks give you a picture of place value. A small square, called a unit, stands for 1 one. A long rod, called a ten, is made of ten units stuck together. A large flat, called a hundred, is made of ten rods stuck together. Counting how many flats, rods, and units you see tells you the hundreds, tens, and ones digits.

Matching pictures like this to written numbers is exactly the skill covered in matching place value models to numbers, so it's worth practicing both together.

Example 1: Identify the hundreds, tens, and ones digits in 472.

Reading left to right: 4 is in the hundreds place, 7 is in the tens place, and 2 is in the ones place. So 472 has 4 hundreds, 7 tens, and 2 ones.

Example 2: Identify the hundreds, tens, and ones digits in 908.

Here the tens digit is 0, meaning there are no tens. The number has 9 hundreds, 0 tens, and 8 ones. It's easy to skip over a 0, but it still holds its own place in the chart.

Example 3: Which digit tells you the tens in 630?

Counting from the right, 0 is ones, 3 is tens, and 6 is hundreds. The tens digit is 3, giving 3 tens, or 30.

A frequent error is mixing up the position of a digit with its actual value. For example, in 356 the digit 5 is not "5", it represents 5 tens, or 50. Another common slip is forgetting that a 0 still fills a place; in 908, the 0 must stay in the tens spot so the 9 and 8 land in the correct hundreds and ones positions. If you'd like more practice converting between how a digit is written and what it's worth, see converting between place values up to 999.

To identify hundreds, tens, and ones in any number up to 999, look at the digit farthest right first (ones), then the digit to its left (tens), then the digit to the left of that (hundreds). Practicing with place value charts and base ten blocks will make this automatic, and it sets you up well for expanded form and regrouping later on.

Related lessons

• Math 2