Using Inverse Operations to Check Answers in 11+ Maths
21 October 2026
What are inverse operations
Inverse operations are pairs of maths actions that undo each other. For example, addition and subtraction are opposites, as are multiplication and division.
Key insight: Understanding inverse operations helps children check their answers and solve equations with confidence.
Why checking answers matters
When a child solves a calculation, using the inverse operation lets them work backwards to see if their answer is correct. This skill is useful for 11+ exams, where accuracy is key.
Worked example: addition and subtraction
Suppose your child solves 58 + 27 = 85.
To check, use subtraction: 85 - 27 = 58.
Because the answer matches the original number, the calculation is correct.
Worked example: multiplication and division
Imagine the question is 7 × 6 = 42.
Check with division: 42 ÷ 6 = 7.
Since you get back to the starting number, the answer is correct.
What does this mean for your child
If the answer does not match the starting number when using the inverse, it is time to review the steps. Practising this method builds accuracy and confidence in 11+ maths.
