The idea, step by step
An empty place still matters
Zero can show that a place has no groups. In 407 there are 4 hundreds, no tens and 7 ones. We write the zero so the 7 stays in the ones place.
| Number | Hundreds | Tens | Ones |
|---|---|---|---|
| 407 | 4 | 0 | 7 |
| 470 | 4 | 7 | 0 |
| 47 | 0 | 4 | 7 |
Read before you write
Say which groups you need before writing a number. Six hundred and eight needs 6 in the hundreds place and 8 in the ones place. The tens place is empty, so write 608. A final zero is also important: 60 and 6 have different values.
A common trap
Leaving out the zero and writing 58 for five hundred and eight.
Instead: 58 has only 5 tens. Write 508 to show 5 hundreds and no tens.
See the thinking
No tens
Write 5 hundreds and 9 ones as one number.
- Write 5 in the hundreds place.
- There are no tens, so put 0 in the tens place; write 9 in ones.
Two numbers, different places
How is 320 different from 302?
- 320 has 3 hundreds, 2 tens and no ones.
- 302 has 3 hundreds, no tens and 2 ones.
Check your understanding
What does the zero in 704 tell us?
Show answer
There are no tens.
The 7 is hundreds, the zero is tens and the 4 is ones.
Your turn
6 questions · Work at your own pace.
Read the questions online
- Write 6 hundreds and 4 ones as one number.
- Write 8 hundreds and 3 tens as one number.
- What does the zero in 205 show?
- Which is seven hundred and six: 76, 706 or 760?
- Write a three-digit number with 4 hundreds and zeros in both other places.
- Are 90 and 9 equal? Explain.
Read the worked solutions
- Write 6 hundreds and 4 ones as one number.
The tens place needs 0.
604 - Write 8 hundreds and 3 tens as one number.
There are no ones, so the final digit is 0.
830 - What does the zero in 205 show?
205 = 200 + 0 + 5.
No tens. - Which is seven hundred and six: 76, 706 or 760?
It has 7 hundreds and 6 ones, with no tens.
706 - Write a three-digit number with 4 hundreds and zeros in both other places.
4 hundreds + 0 tens + 0 ones = 400.
400 - Are 90 and 9 equal? Explain.
9 tens are worth ten times as much as 9 ones.
No. 90 is 9 tens; 9 is 9 ones.
Curriculum reference & lesson scope
Australian Curriculum v9 and SA Curriculum Mathematics
Reading/ordering numbers; hundreds/tens/ones; zero; regrouping and renaming.
Official curriculum source ↗