Mathematics · Grades 1–2
Tens and ones
A group of ten can be exchanged for ten ones.
The key idea
A group of ten can be exchanged for ten ones.
number = 10 × tens + ones
Worked examples
Write the number with 8 tens and 1 ones.
8 × 10 + 1 = 81
81
Write the number with 5 tens and 4 ones.
5 × 10 + 4 = 54
54
Try it yourself
Write the number with 3 tens and 8 ones.
Write the number with 8 tens and 9 ones.
Check your understanding
Answers and marking notes
- 38
3 × 10 + 8 = 38
- 89
8 × 10 + 9 = 89
Further reading and review references
These are reference links, not copied exercises, institutional endorsement or proof of independent review.
Learning preview · teacher review required. Grade bands are approximate, not official curriculum alignment.