The idea, step by step
Keep counting across tens
From twenty, count twenty-one, twenty-two and onwards to twenty-nine, then thirty. Use the next tens names as you continue: forty, fifty, sixty, seventy, eighty and ninety. After each new ten, count the extra ones in order.
After 99 comes 100. Keep the hundred and count the extra ones: 101 is one hundred and one, 102 is one hundred and two.
When you reach 109, the next number is 110, one hundred and ten. It does not jump to 200.
Say it, then write it
One hundred and sixteen is written 116. The digits stay in that order.
Point to each number as you count. Saying one number for each step helps you avoid missing a number.
A common trap
Writing 1010 for one hundred and ten.
Instead: One hundred and ten is 110. The zero shows there are no extra ones.
See the thinking
Crossing a ten
What number comes just after 109?
- Count one more than 109.
- The nine extra ones become another ten.
- The next number is 110.
Read a short count
Read 117, 118, 119 and 120 aloud.
- 117 is one hundred and seventeen.
- 118 and 119 continue the count.
- 120 is one hundred and twenty.
Check your understanding
What comes just after 119?
Show answer
120
Counting one more takes 119 to 120.
Your turn
6 questions · Work at your own pace.
Read the questions online
- Write the number after 99.
- Write the missing number: 103, 104, __, 106.
- Write one hundred and twelve in digits.
- Say 108 in words.
- Write the next three numbers after 117.
- Write the missing numbers: 119, __, 121, __, 123.
Read the worked solutions
- Write the number after 99.
Count one more: 99, 100.
100 - Write the missing number: 103, 104, __, 106.
Count one more at each step.
105 - Write one hundred and twelve in digits.
One hundred plus twelve is written 112.
112 - Say 108 in words.
There are no extra tens.
One hundred and eight. - Write the next three numbers after 117.
Add one each time.
118, 119, 120 - Write the missing numbers: 119, __, 121, __, 123.
Count onwards without skipping a number.
120, 122
Curriculum reference & lesson scope
Australian Curriculum v9 and SA Curriculum Mathematics
Year 1 counting, place value and partitioning.
Official curriculum source ↗