Year 4 - Maths
Review using column subtraction with regrouping from hundreds to tens
Review of column addition and subtraction
Study Hub
Study Guides
This pupil-friendly study guide includes a unit summary, clear notes, common mistakes, and quick questions with answers.
Unit Summary
In this unit pupils will revisit column addition with regrouping and column subtraction with exchanging to solve problems.
Lesson Summary
You will learn to use column subtraction, including regrouping from the hundreds to tens.
Key Notes
- Regroup when the ones or tens digit of the subtrahend is greater than the ones or tens digit of the minuend.
- Regroup a ten into 10 ones.
- Regroup a hundred into 10 tens.
- If the tens digit of the minuend is a zero, you need to regroup the hundreds before you can regroup the tens.
Vocabulary To Learn
- Column subtraction: Column subtraction is a way of subtracting numbers by writing a number below another.
- Regroup: The process of unitising and exchanging between place values is known as regrouping.
Common Mistakes To Avoid
- Pupils may not think regrouping is needed if the tens are the same digit, but regrouping in the ones can mean regrouping in the tens.
3 Quick Questions (With Answers)
1. Solve this in steps: explain the method from this lesson and why each step matters.
Regroup when the ones or tens digit of the subtrahend is greater than the ones or tens digit of the minuend. Regroup a ten into 10 ones.
2. Use this key word in a maths sentence and explain it clearly. 'Column subtraction'
Column subtraction is a way of subtracting numbers by writing a number below another. Use this word when showing your method, then check your final answer is reasonable.
3. Spot and fix this common maths mistake.
Mistake: Pupils may not think regrouping is needed if the tens are the same digit, but regrouping in the ones can mean regrouping in the tens. Correction: Share examples where regrouping 1 ten as 10 tens means that regrouping is also needed in the tens (e.g. 345 - 148).
More Lessons In This Unit
- Decide on the most efficient subtraction strategy, including column subtraction Study Guide
- Review adding 2-digit numbers using column addition without regrouping Study Guide
- Review adding 3-digit numbers using column addition without regrouping Study Guide
- Review and use knowledge of place value to correctly lay out column addition Study Guide
- Review column addition and identify the addends and sum Study Guide
- Review identifying the minuend and subtrahend in column subtraction Study Guide
- Review using column addition to add 2- and 3-digit numbers by regrouping ones Study Guide
- Review using column addition to add 2- and 3-digit numbers by regrouping tens Study Guide
- Review using column addition with regrouping in the ones and tens columns Study Guide
- Review using column subtraction to subtract without regrouping Study Guide
- Review using column subtraction with regrouping from tens to ones Study Guide
- Review using known facts and strategies to accurately and efficiently use and check column addition Study Guide
- Use column addition to solve problems in different contexts Study Guide
- Use knowledge of column addition to solve problems in a range of contexts Study Guide
Browse all guides in the Year 4 Maths guide library.