Explore · Mathematics · Number Representation & Place Value

The two digits of a two-digit number

Understand that the two digits of a two-digit number represent amounts of tens and ones

ages 6 to 78 practice questionsvideo included

What a learner can do afterwards

Explain that in 47, the 4 represents 4 tens (40) and the 7 represents 7 ones
Use base-ten blocks to show a two-digit number as tens and ones
Identify the tens digit and ones digit in any two-digit number

The lesson

A two-digit number has two digits, and each one has a job. The digit on the left counts tens. The digit on the right counts ones.

Tap each block and count out loud.

Twenty is 2 tens and 0 ones. Each group of ten blocks is one ten.

Try it together

Look at 47. The 4 is in the tens spot, so it means 4 tens, which is 40. The 7 is in the ones spot, so it means 7 ones. Forty plus seven is forty-seven.

Good to know

Read a two-digit number from left to right: tens digit first, then ones digit. Swap them and you get a different number.

The left digit tells you the tens, the right digit tells you the ones, and together they make the number.

Watch it

Where it sits

Learn first

A Ten Is Ten Ones The teen numbers

This opens up

Fluent addition and subtraction A Hundred Is Ten Tens Representing Numbers Mental addition and subtraction (age 6+)The three digits of a three-digit number Shape patterns Adding within 100 Adding and subtracting tens mentally Place value understanding and number facts 10 More or 10 Less Counting forwards and backwards (age 6+)Comparing and ordering numbers

Where this leads

Jobs that lean on this skill. Follow one to see everything it is built on.

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Then practise

8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.