🔢 Maths

Tens and Ones

Ages 7–9

You will learn

Know what each digit in a 2-digit number is worth, and use tens and ones to compare numbers.

Before you start

Counting to 100, and counting in 10s (10, 20, 30…).

Quick answer

In a 2-digit number, the left digit tells you how many tens and the right digit tells you how many ones. In 47, the 4 is worth 40 (4 tens) and the 7 is worth 7 (7 ones).

Let’s learn

Numbers are made of digits. In a 2-digit number, where a digit sits tells us what it is worth.

Tens Ones
4 7
  • The 4 is in the tens place. It is worth 40.
  • The 7 is in the ones place. It is worth 7.

So 47 = 40 + 7.

Example

🟩🟩🟩🟩🟩🟩🟩🟩🟩🟩 (a ten) 🟩🟩🟩🟩🟩🟩🟩🟩🟩🟩 (a ten) 🟩🟩🟩 (3 ones)

2 tens and 3 ones = 20 + 3 = 23.

Comparing numbers

To see which number is bigger, look at the tens first.

  • 54 or 45? 54 has 5 tens, 45 has 4 tens. So 54 is bigger.
  • If the tens are the same, look at the ones: 36 is bigger than 32.

Check what you know

Choose an answer, then press Check. You can try again if you need to.

  1. 1 In the number 47, what is the 4 worth?
  2. 2 In the number 63, how many ones are there?
  3. 3 What number is 5 tens and 2 ones?
  4. 4 Which number has 8 tens?
  5. 5 What is 30 + 9?
  6. 6 Which number is bigger: 71 or 68?

Try this next

Bundle straws or sticks into groups of 10 with a hair band. Make numbers like 34 using bundles of ten and single sticks.