Worked example
26 October 2026
One-step missing number problems help your child spot the unknown part in a simple equation. These questions often use addition or subtraction, and your child needs to find the number that makes the equation true.
Find the missing number in □ + 7 = 15
Step 1: We want to find the number that, when added to 7, gives 15.
Step 2: Use the inverse operation. Take 15 and subtract 7.
15 - 7 = 8
Step 3: Check your answer. 8 + 7 = 15
The missing number is 8.
Click or tap on the number line to answer
After working through this example, your child will recognise how to use inverse operations to find a missing number. The next step is to practise similar questions, building confidence and speed with this type of maths.com uk problem.
