How to explain estimate differences in estimate & check to your student: Example question
30 October 2026
Estimating differences is a helpful way for children to check if their answers are sensible before working out the exact calculation. This approach builds confidence and helps your child spot mistakes early.
Example question
Estimate the difference between 84 and 37, then check your answer.
Step 1: Estimate the numbers
Round 84 to 80.
Round 37 to 40.
Step 2: Find the estimated difference 80 - 40 = 40
Step 3: Work out the exact difference 84 - 37 = 47
Step 4: Check your answer
The exact difference (47) is close to the estimate (40).
This means your answer is reasonable.
Key insight: When your child estimates and then checks, they learn to judge if an answer is reasonable. Now they can recognise when an answer is close to their estimate and know they are on the right track. Try more estimate differences questions for extra practice.
