Inverse: addition undoes subtraction
Recognise and use the inverse relationship between addition and subtraction to check calculations and solve missing-number problems
Teaching approaches
Gakuva’s recommended starting approach is selected. You can still compare every option.
1 approach
If your child works out 13 + 5 = 18, can they immediately use that to say '18 − 5 = 13' — without having to work the subtraction out all over again?
Recognise and use the inverse relationship between addition and subtraction to check calculations and solve missing-number problems
Learning resources
Reviewed external links that reinforce this concept. They do not replace Gakuva’s teaching approach.
No reviewed resources for this concept yet.
The teaching approach above still stands. Curated practice links — and later lock-ranked options — will appear here as the shelf fills.
Explore the learning path
1 before · 3 after
This concept
Check understanding
- Check 15 + 7 = 22 by calculating 22 − 7 = 15
- Use the inverse to solve: □ + 9 = 14, so □ = 14 − 9 = 5
- Explain that addition and subtraction 'undo' each other
“If your child works out 13 + 5 = 18, can they immediately use that to say '18 − 5 = 13' — without having to work the subtraction out all over again?”
Curriculum record
- Type
- Conceptual
- Subject
- Mathematics
- Domain
- Addition & Subtraction
- Age range
- Ages 6–7
Standards